Schmidt reaction, with

In addition to the present method,2 1-amino-1-methylcyclo-hexane has been synthesized by the following procedures Ritter reaction, e.g., with 1-methylcyclohexanol (76%, 67%)3i 4 or 1-methylcyclohexene (35%,) 4 5 Hofmann reaction with 1-methyl-cyclohexanecarboxamide (80% as hydrochloride) 6 reduction of 1-methyl-l-nitrocyclohexane (63%) 6 Schmidt reaction with 1-methylcyclohexanecarboxylic acid (42%).6... 

The synthesis of TATB (14) from the reaction of 2,3,4,5,6-pentanitroaniline (31) with ammonia has been reported. " In one route, 2,3,4,5,6-pentanitroaniline (31) is synthesized from the nitration of 3,5-dinitroaniline (30) " the latter is obtained from the selective reduction of TNB ° or via a Schmidt reaction with 3,5-dinitrobenzoic acid. Another route to 2,3,4,5,6-pentanitroaniline (31) involves the selective reduction of TNT (1) with hydrogen sulfide in ammonia followed by nitration of the resulting 4-amino-2,6-dinitrotoluene (46), during which the methyl group is lost by oxidation-decarboxylation. 

Anm. wahrend d. Korr. 6-Methoxy-l-tetralon, in dem dor clcktronische Eliekt des Aromaten dem in (7) vergleichbar ist, liefert jedoch iibcrvvicgend das Laktam mit CO am Bcnzolring [analog (14)] Evans, D. u. I. M. Lockhart, The Schmidt reaction with aromatic ketones. J. Cheni. Soc. [London] 1965, 4806. 

The reaction sequence - including subsequent reaction with water which leads to amines - is named the Curtius Reaction. This reaction is similar to the Schmidt Reaction with acids, differing in that the acyl azide in the present case is prepared from the acyl halide and an azide salt. 

Scheme 11/14. Mechanism of the Schmidt reaction with ketones [77].

Schmidt reactions with sodium azide and strong acids, if they occur through tetrahedral reaction intermediates, lead primarily to nitrogen insertion adjacent to methylene rather than methine groups. There are no really satisfactory reasons for preferential methylene migration in this case [81]. 

The Schmidt reaction with the dienone 11/102 (Scheme 11/15) yields the 1,4-thiazepine, 11/103. Treatment of its dihydroderivate, II/104, gives exclusively the enlargement product 11/105, in which the methylene group migrated [82]. A similar reaction can be observed if the synthetic ergot alkaloid precursors of type 11/106 are treated with in situ generated hydrazoic acid. Again no trace of the isomeric lactam can be observed [83]. 

Many attempts have been made to carry out the Schmidt reaction with alkyl or aryl azides in place of hydrazoic acid in the presence or absence of catalysing acids and either in the cold or on heating. Most have been fruitless although a few apparently valid claims are recorded. One is that treatment of acetophenone with methyl azide led to a trace of acetanilide and since the reagent was strictly free of hydrazoic acid and was not hydrolysed or otherwise split under the reaction conditions some demetliylation must have occurred at... 

Koldobskii, G. I., Ostrovskii, V. A., Gidaspov, B. V. Schmidt reaction with aldehydes and carboxylic acids. Russ. Chem. Rev. 1978,47, 1084-1094. 

Insight has been gained into the mechanism of the Schmidt reaction with acids by the observation that the transformation proceeds most easily with those hindered acids which, in sulfuric acid solution, give rise... 

Migration of Groups in the Schmidt Reaction with Unsymmetrical Ketones... 

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