THE STEREOCHEMISTRY OF THE INTRAMOLECULAR ELECTROPHILIC ATTACK OF AN ALDEHYDE ON A CARBON-TIN BOND

Article abstract of DOI:10.1016/S0040-4020(01)87383-X

The cyclopentane-forming reaction (20-43) of (4RS,5SR)-2,2,4-trimethyl-5-trimetstannylhexanal takes place with retention of configuration at the carbon atom undergoing electrophilic substitution, in contrast to similar cyclopropane-forming reactions (e.g. 47-48), which take place with inversion of configuration.The hydride transfer (24-45) of the 4RS,5RS diastereoisomeric hexanal takes place from a conformation with hydride anti to the stannyl group.In the case of reacions which might have formed four-membered rings, fragmentation takes place (16-28 and 17-30).The presence of a phenyl ring on the carbon carrying the stannyl group interferes with the reactions designed to test the stereochemistry of the S_E2 reaction, diverting the reaction to the formation of tetralins (10-26 and 34-38) or benzcycloheptenes (34-37).