No abstract

An efficient and a facile route to spiro-β-lactams is described. 3-allyl-3-methylthio-β-lactams, which are synthesized through a Lewis acid mediated C-3 alkylation of the trans-3-chloro-3-methylthio-βlactams, undergo a facile intrasulfenyl cyclization reaction in the presence of halogens like bromine and iodine to give spiro β-lactams in good yield. These halospiro-β-lactams are then subjected to dehalogenation reaction using Raney-nickel. The resulting spiro-β-lactams are further transformed into their sulfinyl and sulfonyl derivatives by using m-chloroperbenzoic acid as an oxidant.

An operationally simple, highly efficient and stereoselective method for oxidation of trans‐3‐phenylthio‐β‐lactams to trans‐3‐phenylsulfinyl‐β‐lactams is reported. High selectivity and yields were obtained under mild conditions. The probable mechanistic scheme for the formation of oxidized product is proposed.

No abstract

An effective and stereoselective synthesis of 3-(1-methyl/phenylallyl)-3-phenylthio-β-lactams (3/4) using substituted allylsilane and Lewis acid is described. The reaction leads to the formation of a mixture of C-3 substituted allyl β-Lactams. However, these compounds on desulphurisation using tri-n-butyltinhydride and Raney Ni provide two separable diastereomers of the reduced product.