HOFMANN REARRANGEMENT UNDER MILDLY ACIDIC CONDITIONS

HOFMANN REARRANGEMENT UNDER MILDLY ACIDIC CONDITIONS, 66. 132... 

HOFMANN REARRANGEMENT UNDER MILDLY ACIDIC CONDITIONS USING [I.I-BIS(TRIFLUOROACETOXY)]-IODOBENZENE. CYCLOBUTYLAMINE HYDROCHLORIDE FROM CYCLOBUTANECARBOXAMIDE... 

The oxidative Hofmann rearrangement of primary carboxamides occurs by use of lead tetraacetate (LTA) and several hypervalent organoiodine compounds IF5 (28), PhI(OCOCP3)2 (29), PhI(OH)OTs (30) and PhIO (31) under mildly acidic conditions. 

Reagent for effecting the Hofmann rearrangement of amides under mildly acidic conditions used esp. for peptides. Used in the spectrophotometric and densitometric anal, of amines and hydrazines. Mp 124-126°. 

A study of the photoaddition of formamide to olefins was undertaken with the aim of finding a new process for converting olefins to higher amides and possibly further to amines by reduction or by the use of the Hofmann rearrangement. Since hydrolysis of the amides to the corresponding carboxylic acids can be effected by standard procedures, this reaction provides a new process for carboxylation of olefins under mild conditions at room temperature. A similar reaction has been shown to take place in a thermal process, using peroxides as initiators (60). 

Conversions of compounds 116, 120 and 123 into IP-2-ones described above belong to Hofmann-, Curtius- and Lossen-type reactions. Therefore the parent amides, hydroxamic acids and o-aminopyridinecarboxylic acid azides, may formally be regarded as derivatives of monoaminopyridines. The above compounds rearrange into o-diamines with various degrees of ease, while benzenesulphonate 121 is transformed into intermediate isocyanate 122 under extremely mild conditions (68JOC2543). 

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