Search results
Results from the WOW.Com Content Network
The Hofmann rearrangement (Hofmann degradation) is the organic reaction of a primary amide to a primary amine with one less carbon atom. [ 1 ] [ 2 ] [ 3 ] The reaction involves oxidation of the nitrogen followed by rearrangement of the carbonyl and nitrogen to give an isocyanate intermediate.
The Hofmann–Martius rearrangement in organic chemistry is a rearrangement reaction converting an N-alkylated aniline to the corresponding ortho and / or para aryl-alkylated aniline. The reaction requires heat, and the catalyst is an acid like hydrochloric acid .
The Hofmann rearrangement is a decarbonylation reaction whereby an amide is converted to an amine by way of an isocyanate intermediate. It is usually carried out under strongly basic conditions. It is usually carried out under strongly basic conditions.
The Cope elimination is very similar to the Hofmann elimination in principle, but occurs under milder conditions. It also favors the formation of the Hofmann product, and for the same reasons. [3] An example of a Hofmann elimination (not involving a contrast between a Zaitsev product and a Hofmann product) is the synthesis of trans-cyclooctene. [4]
The reaction mechanism is that of the related Hofmann degradation. [2] Weermann degradation mechanism of Hydroxy-Carbonsäureamide. At first the carbonic acid amide (1) reacts with the sodium hypochlorite. After the separation of water and chloride an amine with a free bond is built 2. The intermediate (3) is generated by rearrangement. In the ...
PIFA can be used to carry out the Hofmann rearrangement under mildly acidic conditions, [11] rather than the strongly basic conditions traditionally used. [ 12 ] [ 13 ] The Hofmann decarbonylation of an N -protected asparagine has been demonstrated with PIDA, providing a route to β-amino- L - alanine derivatives.
R. P. Deshpande and U. R. Nayak [37] reported that the Hofmann–Löffler–Freytag reaction is applicable to the synthesis of pyrrolidines containing a longifolene nucleus, e.g. 62. An outstanding application of the Hofmann–Löffler–Freytag reaction is found in the preparation of the steroidal alkaloid derivatives. J.
August Wilhelm von Hofmann (8 April 1818 – 5 May 1892 [2]) was a German chemist who made considerable contributions to organic chemistry. His research on aniline helped lay the basis of the aniline-dye industry, and his research on coal tar laid the groundwork for his student Charles Mansfield's practical methods for extracting benzene and toluene and converting them into nitro compounds and ...