Allylic trichloroacetimidates 3.3 sigmatropic rearrangement

Allyl imidate esters undergo [3,3] sigmatropic rearrangements to A -allyl amides. Trichloroacetimidates can be easily made from allylic alcohols by reaction with trichloroacetonitrile. The rearrangement then provides trichloroacetamides of iV-allyl-amines.176 177... 

The Overman rearrangement, a thermal [3,3]-sigmatropic rearrangement of allylic trichloroacetimidates, is an attractive procedure for the preparation of ally] amines from allyl alcohols (Eq. (4)) [7]. 

The first step in this reaction is formation of the allyl trichloroacetimide 8 formed from allyl alcohol 3 by reaction with trichloroacetonitrile. The allyl amides 9 are formed by the [3,3]-sigmatropic rearrangement of 8, followed by hydrolysis. The reaction proceeds with good yield for primary and secondary amides however, for products where the amide nitrogen is bound to a tertiary carbon atom the yields are generally low. 

L. E. Overman, Thermal and mercuric ion catalyzed [3,3]-sigmatropic rearrangement of allylic trichloroacetimidates. 1,3-Transposition of alcohol and amine functions,. /. Am. Chem. Soc., 96 (1974) 597-599. 

Nagashima, H., Wakamatsu, H., Ozaki, N., Ishii, T., Watanabe, M., Tajima, T., Itoh, K. Transition metal catalyzed radical cyclization new preparative route to y-lactams from allylic alcohols via the [3.3]-sigmatropic rearrangement of allylic trichloroacetimidates and the subsequent ruthenium-catalyzed cyclization of N-allyltrichloroacetamides. J. Org. Chem. 1992, 57, 1682-1689. 

Thermal and mercury(ii)-catalysed [3,3]sigmatropic rearangement of allylic trichloroacetimidates and allylic pseudo-ureas" e.g. geraniol, linalool) are useful for the 1,3-transposition of hydroxy- and amino-groups the former is synthetically preferred. The [2,3]sigmatropic rearrangement of allylic sulphoxides has been used to effect an alkylative 1,3-carbonyl transposition of enones (e.g. carvone). ... 

Conversion of ailylic alcohols into rearranged allylic amines. This transposition can be accomplished by conversion of an allyhc alcohol, for example geraniol (1), into the trichloroacetimidate (2) by treatment with sodium or potassium hydride and then with trichloroacetonitrile (ether, -10° and then 20°). This allylic imidate undergoes a [3.3] sigmatropic rearrangement when... 

Formal [3,3]-sigmatropic rearrangement of the trichloroacetimidate of allylic alcohols to allylic trichloroacetamides, thereby transposing the hydroxyl and amino functions with good chirality transfer ... 

Sigmatropic Rearrangement of Trichloroacetimidates The development of the asymmetric palladium(II)-catalyzed [3,3]-sigmatropic rearrangement of trichloroacetimidates has proven to be a powerful method for the generation of chiral amines from achiral allylic alcohols [12]. In particular, the cobalt oxazoline palladacycles, such as COP-Cl (4), have been shown to be particularly efficient for this transformation (Scheme 5.1) [13]. 

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