SILVER-IODIDE MEDIATED AMINATION REACTION OF ALLYLIC CHLORIDES WITH LITHIUM BIS(TRIMETHYLSILYL)AMIDE - A NEW SYNTHETIC METHOD OF N,N-DISILYLALLYLAMINES VIA LITHIUM AMIDE ARGENTATES

The nucleophilic substitution reaction of allylic chlorides with lithium bis(trimethylsilyl)amide (1) in the presence of silver halides has been studied in detail. Silver iodide (AgI) was found to be most effective for facilitation of the amination reaction. The reaction of alkyl-substituted allylic chlorides proceeded smoothly in S(N)2 fashion to give N,N-disilylallylamines in high yields when 0.1 or 0.5 equiv of AgI was used as an additive, whereas a stoichiometric amount of AgI was indispensable in the reaction of allylic chlorides having a phenyl group. The reaction of geranyl or neryl chloride proceeded with retention of configuration of the C=C bond to give only one isomer 4 or 5, respectively. The oxygen-containing functional groups and chlorine remained intact during the reaction. The reaction of alpha-silylmetallyl chloride 17 proceeded in an S(N)2' manner to afford (Z)-allylamine 18. So as to disclose the active species in the AgI-mediated reaction, the variable low-temperature C-13 NMR experiments using the mixture of AgI and 1 in THF have been performed. It has been suggested that lithium amide argentates such as (Me3Si)2NAg(I)Li (20) and [(Me3Si)2N]2Ag(I)Li2 (21) are formed in the reaction mixture, and the nucleophilicity and basicity of 1 are controlled by forming these species.