A kinetic study on the intramolecular direct radical substitution reaction on tin atoms was undertaken.

Controlling the reactivity of the nitrogen or oxygen nucleophile of an amide group to form C–N or C–O bonds by tuning reaction conditions is one of the most challenging issues in the use of amides in organic synthesis. Both nucleophiles in the amide group can individually participate in reactions, and most reactions employ a substrate-controlled methodology to achieve selectivity. However, in the reaction of α-bromoamides and acrylates, we successfully controlled the reactivity of the nitrogen or oxygen nucleophile of the amide group to afford a lactam via carboamidation or an iminolactone via carbooxygenation, using a copper catalyst system with an appropriate base.

Optically active ent-calystegine B4 was prepared in 13 steps from commercially available chiral L-dimethyl tartrate. The synthesis was achieved by the Michael addition and the aldol reaction of nitromethane to form cycloheptanone in a stereoselective manner. Reduction of the nitro group in the presence of Boc(2)O accomplished an efficient conversion to amino cycloheptanone, which readily afforded the desired ent-calystegine B4.

A one-step conversion of allylic nitro compounds to substituted 2,3-dihydrofurans has been developed. Allylic nitro compounds, which are readily available from nitroalkenes and formaldehyde, underwent a double allylic substitution reaction catalyzed by a palladium complex to give 2,3-dihydrofurans in good yield.