Goodreads helps you keep track of books you want to read.
- El Hombre De Arena Eta Hoffmann Pdf Free
- El Hombre De Arena Movie
- El Hombre De Arena De Hoffmann
- El Hombre De Arena Eta Hoffmann Pdf Online
- El Hombre De Arena Pdf
- El Hombre De Arena
- El Hombre De Arena Eta Hoffmann Pdf Download
El hombre de arena eta hoffmann analysis essay. El hombre de arena eta hoffmann analysis essay. 4 stars based on 153 reviews bvpoker.com Essay. Ways to reduce bullying in schools essay bad luck essay. Essay on brain drain pdf editor rav soloveitchik essays sports marketing essay.
El Hombre De Arena Eta Hoffmann Pdf Free
- Essayez les lunettes de vue, best essay intro ever after high boston latin school harvard admissions essay labor and legality essay writer canada in the 1920s essay importance of education in developing countries essay help creative writing a dream come true essays on leadershipComing out of the closet essay writer. Amy tan essay mother tongue pdf.
- El hombre de arena eta hoffmann analysis essay. December 6, 2018. Conjugaison conditionnel present vouloir indus world school sainikpuri admissions essay accounting research paper pdf educating rita summary essay papers essay on environmental degradation statistics.
Start by marking “El hombre de arena” as Want to Read:
Rate this book
See a Problem?
We’d love your help. Let us know what’s wrong with this preview of El hombre de arena by E.T.A. Hoffmann.
Not the book you’re looking for?Preview — El hombre de arena by E.T.A. Hoffmann
La historia de un hombre obsesionado por la muerte de su padre en extrañas circunstancias durante su infancia y de la que hace responsable a un sórdido personaje, alquimista y protagonista de sus pesadillas infantiles. Lo que interpreta como reencuentro casual con el sórdido alquimista reaviva las frustraciones de la infancia y arrastra al personaje a una espiral autodestr...more
Published July 16th 2013 (first published January 19th 1816)
To see what your friends thought of this book,please sign up.
To ask other readers questions aboutEl hombre de arena,please sign up.
Be the first to ask a question about El hombre de arena
This book is not yet featured on Listopia.Add this book to your favorite list »
Rating details
|
Nov 23, 2009Manybooks rated it really liked it · review of another edition Shelves: book-reviews, fairy-tales-fantasy, folklore-kunstmarchen, german-literature, horror
I read this rather (no very) creepy tale years ago, and while I truly enjoyed and above all appreciated E. T. A. Hoffmann's Der Sandmann, I also do not much feel like a detailed and intense rereading at this time, as the plot, the thematics actually repeatedly produced some rather vivid and glaring nightmares when I perused it, first for a German Romanticism course in undergrad and then later for my PhD Comprehensive Examinations (I still recall that there were dancing mechnical maniacal dolls,...more
Nov 21, 2017Kai rated it liked it · review of another edition
“If, like a bold painter, you had first sketched in a few audacious strokes the outline of the picture you had in your own soul, you would then easily have been able to deepen and intensify the colors one after the other, until the varied throng of living figures carried your friends away and they, like you, saw themselves in the midst of the scene that had proceeded out of your own soul.”
We had to read The Sandman for our literature seminar. I was looking forward to it. I had never read anythin...more
We had to read The Sandman for our literature seminar. I was looking forward to it. I had never read anythin...more
Nov 30, 2016Gerasimos rated it it was amazing · review of another edition
The work of a genius! Very creepy and enjoyable to read, but at the same time extremely intelligent and multilayered.
May 11, 2011 Danielle The Book Huntress (Back to the Books) rated it really liked it · review of another editionRecommends it for: classic horror/dark fantasy readers
Shelves: classic-horror, psychological-horror, robot-cyborg-artificial-enhanced-hu, epistolary-narrative, online-read, short-story, tales-to-chill-your-blood, 2011-reading
The antiquated language and over-wrought prose on offer here will likely turn off some readers. I don’t necessarily prefer this sort of writing, and I don’t care to read it terribly often (despite my enchantment with classic horror and speculative fiction). However, part of me enjoys these elements at the same time as finding them hard to tolerate when I am not in the mood for them. Rather a contradiction, but there you have it. There’s something about the way this taste of antiquity takes me ba...more
Oct 27, 2018Book Wyrm rated it it was amazing · review of another edition
Mr Sandman, don't touch my eyes,
I see through your disguises and lies.
I'll burn your soul, rip out your spleen with a knife,
I'm far too batshit to just get on with my life.
The Sandman really is one odd and off sally; or really two sallies, since the second half seems to have only a passing acquaintance with the first.
I was expecting this to be about a young man chasing an eye eating monster, and was instead wrapped up in a tale of insanity brought on by childhood trauma, leering villains and cha...more
I see through your disguises and lies.
I'll burn your soul, rip out your spleen with a knife,
I'm far too batshit to just get on with my life.
The Sandman really is one odd and off sally; or really two sallies, since the second half seems to have only a passing acquaintance with the first.
I was expecting this to be about a young man chasing an eye eating monster, and was instead wrapped up in a tale of insanity brought on by childhood trauma, leering villains and cha...more
May 28, 2018Zainab rated it really liked it · review of another edition
Mr. Sandman, bring me a dream
Make him the cutest that I’ve ever seen
Give him the word that I’m not a rover
I'm sorry but that's all I can think of right now and now the song's stuck in my head :)))) Toodles!
Make him the cutest that I’ve ever seen
Give him the word that I’m not a rover
I'm sorry but that's all I can think of right now and now the song's stuck in my head :)))) Toodles!
Mar 15, 2019Martin rated it it was amazing · review of another edition
This famous German classic is 200 years old. And yet, with the current research interest in robotics and AI, it's more up to date than ever before.
The events of this short story are up to numerous interpretations - which seem to be a favorite pastime of those studying German literature - but basically 'The Sand Man' is the chronology of a mental illness.
A young college student named Nathanael recalls a traumatic childhood experience after running into a man who reminds him of the person who caus...more
Sep 26, 2015Joseph rated it really liked it · review of another editionThe events of this short story are up to numerous interpretations - which seem to be a favorite pastime of those studying German literature - but basically 'The Sand Man' is the chronology of a mental illness.
A young college student named Nathanael recalls a traumatic childhood experience after running into a man who reminds him of the person who caus...more
Shelves: weird-fiction, classics, fiction-in-translation, gothic-and-supernatural, novellas
Nathanael’s childhood is haunted by the mysterious figure of Coppelius, a lawyer-friend of his father who regularly turns up at their house for night-time alchemical sessions. Nathanael associates Coppelius with the mythical Sandman, the legendary being said to steal the eyes of children who refuse to go to sleep. When Nathanael’s father dies as a result of an experiment gone wrong, this ominous mental link is sealed once and for all. Years later, with Nathanael now a university student, unwelco...more
Apr 03, 2019Peter rated it it was amazing · review of another edition
Brilliant book starting with a kid's fear of the sandman. Problem is the 'sandman' concept never truely disappears but comes again and again haunting Nathanael. Why is advocate Coppelius or the weather glass hawker Coppola associated with 'evil principle'? Is there something supernatural at work and did Coppelius really kill his father? Nathanael insults his soon-to-be wife Clara as 'lifeless automaton' as she gives a rational explanation on his fears. But what about Spalanzani's daughter Olimpi...more
Nov 16, 2014Althea Ann rated it really liked it · review of another edition
About the title story only...
E.T.A. HOFFMANN, The Sandman
(1816).
Remarkably modern-feeling in theme, probably because lately we've had quite a few writers harking back to this kind of story. The sinister traveling merchant Coppelius/Coppola, selling his 'eyes-a' is reflected in “Ilse, Who Saw Clearly” by E. Lily Yu, for example. And of course, the whole steampunk genre loves to explore the idea of clockwork automata.
To a modern reader, the structure of the story flows a bit oddly and unevenly, a...more
Mar 03, 2018Kathrin rated it really liked it · review of another editionE.T.A. HOFFMANN, The Sandman
(1816).
Remarkably modern-feeling in theme, probably because lately we've had quite a few writers harking back to this kind of story. The sinister traveling merchant Coppelius/Coppola, selling his 'eyes-a' is reflected in “Ilse, Who Saw Clearly” by E. Lily Yu, for example. And of course, the whole steampunk genre loves to explore the idea of clockwork automata.
To a modern reader, the structure of the story flows a bit oddly and unevenly, a...more
Shelves: 19th-century, audiobook, classics, germany, short-stories-novellas
Such a short but brilliant book. I remember hating it when I was forced to read it back in school but somehow ended up loving it even back then- I choose to write my final examination about its characters.
Rereading it, I'm still amazed by Nathanael's story. Although the book is rather short, it offers a lot. Beginning with the retelling of a horrible incident in his childhood, it proceeds to show how this early incident shapes his years as a student. Nathanael is the prime example of a youth in...more
Rereading it, I'm still amazed by Nathanael's story. Although the book is rather short, it offers a lot. Beginning with the retelling of a horrible incident in his childhood, it proceeds to show how this early incident shapes his years as a student. Nathanael is the prime example of a youth in...more
Apr 15, 2014Vit Babenco rated it it was amazing · review of another edition
“There is no Sandman, dear child,” replied my mother. “When I say the Sandman's coming, I only mean that you're sleepy and can't keep your eyes open – just as if sand had been sprinkled into them.”
There is something very special in the tales of E.T.A. Hoffmann – two centuries have gone but they still remain enigmatic, startling and morosely nocturnal.
“And now Nathaniel saw that a pair of eyes lay upon the ground, staring at him; these Spalanzani caught up, with his unwounded hand, and flung int...more
Jan 18, 2012Lydia Presley rated it it was amazing · review of another editionThere is something very special in the tales of E.T.A. Hoffmann – two centuries have gone but they still remain enigmatic, startling and morosely nocturnal.
“And now Nathaniel saw that a pair of eyes lay upon the ground, staring at him; these Spalanzani caught up, with his unwounded hand, and flung int...more
Shelves: dark-fiction, 2012, short_stories, fiction, horror
Original review posted here
There is absolutely no reason for people to avoid reading this story. First of all, it’s short – about 30 pages (and the ones I read were TINY pages). Secondly, it’s so. freaking. amazing. Seriously! Read it! Now I’ll tell you why.
For my Seminar in European Literature this semester we are studying the “uncanny” – what the word means, how to define it ourselves, how it’s defined in stories, and we’re reading all sorts of fantastic things like Grimm’s Fairy Tales, Freud’...more
There is absolutely no reason for people to avoid reading this story. First of all, it’s short – about 30 pages (and the ones I read were TINY pages). Secondly, it’s so. freaking. amazing. Seriously! Read it! Now I’ll tell you why.
For my Seminar in European Literature this semester we are studying the “uncanny” – what the word means, how to define it ourselves, how it’s defined in stories, and we’re reading all sorts of fantastic things like Grimm’s Fairy Tales, Freud’...more
Mar 07, 2019Shima Masoumi rated it really liked it · review of another edition
El Hombre De Arena Movie
I started reading Hoffmann with this book and I think it’s a good introduction to his works and his way of thinking. The book is about a guy lost between reality and dreams. In this book he deals with industrialism and what’s happening to us as human beings. Hoffmann’s an early romantic and his way of narrating the story is one of a kind and amazingly symbolic. Freud has written an essay on this book but I don’t really recommend it cause it’s super phallocentrique and in my opinion not really wh...more
Jan 13, 2018Krystal rated it really liked it · 
review of another edition Shelves: owned, myths-and-legends, horror, classics
El Hombre De Arena De Hoffmann
... what did I just read?!
This is so many kinds of disturbing that nightmares are inevitable. How ironic.
I freaking loved it, by the way.
For a short story, there's several layers of creepy, and there's no black and white so part of its genius is in how many questions you're left with at the end.
I want to know MORE.
I mean, surely we've all heard of The Sandman, right? The creep who throws dust in children's faces to get them to sleep?
Well,this delightful little short story, along with my fasci...more
This is so many kinds of disturbing that nightmares are inevitable. How ironic.
I freaking loved it, by the way.
For a short story, there's several layers of creepy, and there's no black and white so part of its genius is in how many questions you're left with at the end.
I want to know MORE.
I mean, surely we've all heard of The Sandman, right? The creep who throws dust in children's faces to get them to sleep?
Well,this delightful little short story, along with my fasci...more
Aug 10, 2015Czarny Pies rated it it was amazing · review of another edition
If you were to read only one story by E.T.A. Hoffman this might be it. The Sandman is one of the three tales to figure in Jacques Offenbach great opera and presents in a very forceful fashion several of the great themes that dominate Hoffman's work.
In this work, Hoffman poses third great questions. The first is what is the effect of childhood fears on our later lives. The second one is why do some individuals pursue illusions when better options in the real world are at hand. The last question i...more
Mar 25, 2018Mina Soare rated it really liked it · review of another editionIn this work, Hoffman poses third great questions. The first is what is the effect of childhood fears on our later lives. The second one is why do some individuals pursue illusions when better options in the real world are at hand. The last question i...more
Shelves: dark, romanticism, mystery, novellas, horror, germany
The Sandman has a bit for everyone, although it’s the dark chocolate pack, not your average Easter basket.
One side of it is that Hoffmann writes tales for adults. Many of us learn to let go of the monsters that would surely come to punish us should we be naughty. Nowhere is the transition as clear as it is here, as Hoffmann builds upon the granny scaring young Nathanael with the story of the Sandman and builds him into a monster that feeds on narcissism, obsession and vanity, when Nathanael beco...more
One side of it is that Hoffmann writes tales for adults. Many of us learn to let go of the monsters that would surely come to punish us should we be naughty. Nowhere is the transition as clear as it is here, as Hoffmann builds upon the granny scaring young Nathanael with the story of the Sandman and builds him into a monster that feeds on narcissism, obsession and vanity, when Nathanael beco...more
Aug 26, 2015Rawan rated it it was amazing · review of another edition
I really enjoyed this. I've never read anything by E.T.A. Hoffmann before (the Sandman is part of my assigned reading for a class I'm taking this semester) but it was a really good read. Reminded me of Frankenstein in a lot of places (Nathanael's actions and letters basically screamed Victor Frankenstein to me as well as the origin of him and Clara's relationship) especially with the whole 'how far can we go with science and technology in terms of humanity' thing that Olimpia represented. The am...more
Jun 04, 2018Ezgi Tülü added it · review of another edition
'If there is a dark power which malevolently and treacherously places a thread within us, with which to hold us and draw us down a perilous and pernicious path that we would never otherwise have set foot on - if there is such a power, then it must take the same form as we do, it must become our very self; for only in this way can we believe in it and give it the scope it requires to accomplish its secret task. If our minds, strengthened by a cheerful life, are resolute enough to recognize alien...more
El Hombre De Arena Eta Hoffmann Pdf Online
May 11, 2016Ava rated it really liked it · review of another edition
I am a German native and used to the style this book was written. However, I did read it in English and have to say this was an excellent translation.
The story itself suited my taste in 'creepy' books. It started with the letters written to Nathaniel's friend Lothar. It made me curious how Hoffmann will unravel the story and if he chose to have a happy ending.
At times I felt Stephen King might have borrowed from him, since it reminded me a bit of his stories.
An entertaining short story with a d...more
The story itself suited my taste in 'creepy' books. It started with the letters written to Nathaniel's friend Lothar. It made me curious how Hoffmann will unravel the story and if he chose to have a happy ending.
At times I felt Stephen King might have borrowed from him, since it reminded me a bit of his stories.
An entertaining short story with a d...more
Nov 20, 2016Vienna rated it really liked it · review of another edition
El Hombre De Arena Pdf
I had my eyes on it for a while (my plan was to read in German back when I had to read some German novels; glad I didn't read it back then though, because a) I don't know that much German and b) I think it's even better in English (I can't compare it though, but I mean that I understand it now more I think than when I read it in German). KarinaE (over at Booktube) read it and ever since I wanted to read it too, so I was really excited when I found out it was going to be published in this edition...more
Jul 20, 2018Edoardo Albert rated it really liked it · review of another edition
Superbly creepy while, by modern sensibilities, occasionally hysterically overwrought story. Plus, being only 64 pages long, it's a brilliant way to catch up on the Goodreads reading challenge if you're falling behind schedule!
Oct 15, 2018Tamsien West (Babbling Books) rated it liked it · review of another edition
A perfect Halloween read, short and creepy. There wasn't much to this story beyond a dark twist on the Sandman folk tale, but it mostly worked.
Dec 05, 2015Sam rated it really liked it · review of another edition
This is a disturbing and haunting tale told in the classic Gothic style that leaves more to the imagination to the reader than modern stories and is all the more chilling as a result. The story starts with Nathanael recounting some of his childhood memories of Coppelius, a man who used to visit his father regularly to conduct strange alchemical experiments which were linked to his death. These memories have haunted Nathanael ever since and come back with force when an Italian and his daughter mo...more
Jan 05, 2008Darryl Knudsen rated it really liked it · review of another edition
Great fantastic story-telling by a troubled man. Science and technology versus magic, madness, life and death -- key themes from this Romantic period German author. Who is really sane? And whom can you trust?
Eyeglasses, telescopes, mirrors, and other optically refractive devices abound as symbols of the inescapbability of perspective in observation (nothing can be viewed directly or understood objectively and without bias). And automatons (another key period device) are present as technology be...more
Eyeglasses, telescopes, mirrors, and other optically refractive devices abound as symbols of the inescapbability of perspective in observation (nothing can be viewed directly or understood objectively and without bias). And automatons (another key period device) are present as technology be...more
Nov 04, 2017John rated it really liked it · review of another edition
I have never read any of ETA Hoffmann and this gothic German horror tale is a good introduction. Nathanael’s slow road to madness brought about by his fathers death to who he saw as the Sandman. The Sandman is a bogeyman who sprinkles sand on children’s eyes and they pop out if the child does not go to sleep. I am glad my mum left this fairy tale out of her stories when I was a child! I cannot help thinking insomnia could be linked to a few fairytales.
Nathaniel has a loving girlfriend and goes...more
Jun 21, 2015Katriina ❆ rated it liked it · review of another editionNathaniel has a loving girlfriend and goes...more
Shelves: literature, the-germans, in-original-language
I have long feared reading books by E.T.A. Hoffmann, as his alias sounds rather off-putting and pompously self-centred (which I really don't like in writers). And also because my terrible German teacher LOVES E.T.A. Hoffmann. Then, a good friend who I trust a lot when it comes to books recommended me the Sandman, and I thus decided to follow his example and read it, and I really don't regret it. The language E.T.A. used is beautiful, the book is kinda creepy and has the kind of 'happily ever aft...more
Oct 12, 2012Gina rated it it was ok · review of another edition
Honestly, I'm not even sure what to make of The Sand-Man at this point. So, I won't post much of a review except to say that I found it kind of strange.
Dec 14, 2014Olga Kowalska (WielkiBuk) rated it really liked it · review of another edition
Deeply unsettling, disturbing and even terrifying in the darkness... A weird story of childhood nightmares that come to life many years later.
Aug 04, 2019Noninuna rated it liked it · review of another edition
A child was told a story about a bogeyman which is know as The Sandman. How he would come and took children who're not asleep when they're supposed to. Nathanael recalls the story in a letter he wrote to his friend back home and tells him how the The Sandman is an actual person and what happened when he was too curious about the man back when he was a child. First portion of the book is in letters between Nathanael our MC and his friend who he grew up with. The latter portion is about he, himsel
...moreThere are no discussion topics on this book yet.Be the first to start one »
Recommend It | Stats | Recent Status Updates
See similar books…
See top shelves…
481followers
Ernst Theodor Wilhelm Hoffmann, better known by his pen name E. T. A. Hoffmann (Ernst Theodor Amadeus Hoffmann), was a German Romantic author of fantasy and horror, a jurist, composer, music critic, draftsman and caricaturist. His stories form the basis of Jacques Offenbach's famous opera The Tales of Hoffmann, in which Hoffman appears (heavily fictionalized) as the hero. He is also the author of...more
“Perhaps, too, you will then believe that nothing is more wonderful, nothing more fantastic than real life, and that all that a writer can do is to present it as 'in a glass, darkly'.” — 12 likes
El Hombre De Arena
“But if, like a bold painter, you had first sketched in a few audacious strokes the outline of the picture you had in your own soul, you would then easily have been able to deepen and intensify the colors one after the other, until the varied throng of living figures carried your friends away and they, like you, saw themselves in the midst of the scene that had proceeded out of your own soul.” — 10 likes
More quotes…El Hombre De Arena Eta Hoffmann Pdf Download
Hoffmann Rearrangement Amber Julius Aroo Aroosa sa Shah Shahid id Faisal Jamil CHEM 443, January 16, 2012 Forman Christian College
Presentation
Outline
Biography
Major Discoveries
Similar Reactions
Reaction Scheme and Mechanism
Examples
Applications of Hoffmann Rearrangement Reaction
Biography
of August Wilhelm von Hoffmann Born
8 April 1818 Giessen, Germany
Alma mater University of Gottingen
Doctoral advisor Justus von Liebig Doctoral students Richard Abegg Adolf Pinner Fritz Haber Karl Friedrich von Auwers Rudolf Hugo Nietzki Ferdinand Tiemann Eugen Bamberger
Died 5 May 1892 (aged 74)
Berlin, Germany
Major Discoveries
Hofmann was the first to introduce molecular models into his public lectures around 1860
Hofmann elimination
Hofmann¶s rule
Hofmann rearrangement
Similar Reactions
Citrus Rearrangement
Lossen
Rearrangement
Schmidt
Rearrangement
Reaction Scheme
Amide reacts with Br 2 and base
Rearranges to lose carbonyl carbon making chain 1 carbon shorter
First published 1881 Hofmann, A. W. Chem. Ber. 1881, 14, 2725.
Gives high yields of arylamines and alkylamines
Hoffmann Rearrangement of Amides
In
the presence of a strong base, primary amides react with chlorine or bromine to form shortened amines, with the loss of the carbonyl carbon atom. This reaction, called the H offmann rearrangement , is used to synthesize primary and aryl amines. The Hofmann rearrangement of 10 amides provides 10 amines exclusively, with no contamination from 20 or 30 amines. This reaction also can be useful for shortening a carbon chain, which explains why it is sometimes referred to as a H offmann degradation.
Mechanism of the Hofmann Rearrangement: Steps 1 and 2
Mechanism of the Hofmann Rearrangement: Steps 3 and 4
Summarizing
the Hoffmann rearrangement mechanism
In
the Hofmann rearrangement, an unsubstituted amide is treated with sodium hypobromite (or sodium hydroxide and bromine, which is essentially the same thing) to give a primary amine that has one carbon fewer than the starting amide. The actual product is the isocyanate, but this compound is seldom isolated since it is usually hydrolyzed under the reaction conditions. The R group may be alkyl or aryl, but if it is an alkyl group of more than about six or seven carbons, low yields are obtained unless Br 2 and NaOMe are used instead of Br 2 and NaOH. Another modification uses NBS/NaOMe. Under these conditions the product of addition to the isocyanate is the carbamate RNHCOOMe, which is easily isolated or can be hydrolyzed to the amine. Side reactions when NaOH is the base are formation of ureas RNHCONHR and acylureas RCONHCONHR by addition, respectively, of RNH 2 and RCONH2 to RNCO. If acylureas are desired, they can be made the main products by using only one-half of the usual quantities of Br 2 and NaOH. Source: Smith.
Another side product, but only from primary R, is the nitrile derived from oxidation of RNH2.
M. B., & March . J. (2007). March¶s Advanced Org anic Chemi stry Reactions, Mechanisms, and Structure. 6th Edition. Chapter 18, 1.2REARRANGEMENTS. p. 1607
Examples of reactions involving Hoffmann rearrangement
Examples of reactions involving Hoffmann rearrangement (Contd.)
Several reagents can substitute for bromine. N-Bromosuccinimide and 1,8-Diazabicyclo[5.4.0]undec-7ene (DBU) can effect a Hofmann rearrangement. In the following example, the intermediate isocyanate is trapped by methanol forming a carbamate. A mild alternative to bromine is also bis(trifluoroacetoxy)iodo)benzene. ( Source: http://www.kuwait-md.org/?q=node/1121 )
Applications of Hoffmann rearrangement reactions
Aliphatic & aromatic amides are converted into aliphatic and aromatic amines, respectively In
the preparations of Anthranilic Acid from Phthalimide
Nicotinic acid is converted into 3-Amino pyridine Synthesis of Symmetrical Ureas by (Diacetoyxiodo)benzeneInduced Hoffmann Rearrangement. ( Dirk Landberg, Markus K al esse)
Presentation
Outline
Biography
Major Discoveries
Similar Reactions
Reaction Scheme and Mechanism
Examples
Applications of Hoffmann Rearrangement Reaction
Biography
of August Wilhelm von Hoffmann Born
8 April 1818 Giessen, Germany
Alma mater University of Gottingen
Doctoral advisor Justus von Liebig Doctoral students Richard Abegg Adolf Pinner Fritz Haber Karl Friedrich von Auwers Rudolf Hugo Nietzki Ferdinand Tiemann Eugen Bamberger
Died 5 May 1892 (aged 74)
Berlin, Germany
Major Discoveries
Hofmann was the first to introduce molecular models into his public lectures around 1860
Hofmann elimination
Hofmann¶s rule
Hofmann rearrangement
Similar Reactions
Citrus Rearrangement
Lossen
Rearrangement
Schmidt
Rearrangement
Reaction Scheme
Amide reacts with Br 2 and base
Rearranges to lose carbonyl carbon making chain 1 carbon shorter
First published 1881 Hofmann, A. W. Chem. Ber. 1881, 14, 2725.
Gives high yields of arylamines and alkylamines
Hoffmann Rearrangement of Amides
In
the presence of a strong base, primary amides react with chlorine or bromine to form shortened amines, with the loss of the carbonyl carbon atom. This reaction, called the H offmann rearrangement , is used to synthesize primary and aryl amines. The Hofmann rearrangement of 10 amides provides 10 amines exclusively, with no contamination from 20 or 30 amines. This reaction also can be useful for shortening a carbon chain, which explains why it is sometimes referred to as a H offmann degradation.
Mechanism of the Hofmann Rearrangement: Steps 1 and 2
Mechanism of the Hofmann Rearrangement: Steps 3 and 4
Summarizing
the Hoffmann rearrangement mechanism
In
the Hofmann rearrangement, an unsubstituted amide is treated with sodium hypobromite (or sodium hydroxide and bromine, which is essentially the same thing) to give a primary amine that has one carbon fewer than the starting amide. The actual product is the isocyanate, but this compound is seldom isolated since it is usually hydrolyzed under the reaction conditions. The R group may be alkyl or aryl, but if it is an alkyl group of more than about six or seven carbons, low yields are obtained unless Br 2 and NaOMe are used instead of Br 2 and NaOH. Another modification uses NBS/NaOMe. Under these conditions the product of addition to the isocyanate is the carbamate RNHCOOMe, which is easily isolated or can be hydrolyzed to the amine. Side reactions when NaOH is the base are formation of ureas RNHCONHR and acylureas RCONHCONHR by addition, respectively, of RNH 2 and RCONH2 to RNCO. If acylureas are desired, they can be made the main products by using only one-half of the usual quantities of Br 2 and NaOH. Source: Smith.
Another side product, but only from primary R, is the nitrile derived from oxidation of RNH2.
M. B., & March . J. (2007). March¶s Advanced Org anic Chemi stry Reactions, Mechanisms, and Structure. 6th Edition. Chapter 18, 1.2REARRANGEMENTS. p. 1607
Examples of reactions involving Hoffmann rearrangement
Examples of reactions involving Hoffmann rearrangement (Contd.)
Several reagents can substitute for bromine. N-Bromosuccinimide and 1,8-Diazabicyclo[5.4.0]undec-7ene (DBU) can effect a Hofmann rearrangement. In the following example, the intermediate isocyanate is trapped by methanol forming a carbamate. A mild alternative to bromine is also bis(trifluoroacetoxy)iodo)benzene. ( Source: http://www.kuwait-md.org/?q=node/1121 )
Applications of Hoffmann rearrangement reactions
Aliphatic & aromatic amides are converted into aliphatic and aromatic amines, respectively In
the preparations of Anthranilic Acid from Phthalimide
Nicotinic acid is converted into 3-Amino pyridine Synthesis of Symmetrical Ureas by (Diacetoyxiodo)benzeneInduced Hoffmann Rearrangement. ( Dirk Landberg, Markus K al esse)