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Ethoxy vinyl esters (EVE:2) were efficient reagents for promoting the asymmetric Pummerer reaction with high enantioselectivity and high yield in contrast to the generally used acid anhydrides. Increasing the electron-donating ability on the R function in EVE 2 tended to increase enantioselectivity. Consequently, effective asymmetric rearrangements were achieved using EVEs 2b,c bearing a methoxybenzoyloxy function.

The attributes of 2,2′-azobis-(2,4-dimethyl-4-methoxyvaleronitrile) (V-70), which is an effective radical initiator at low temperature, in contrast to 2,2′-azobisisobutyronitrile (AIBN) are described.

α-Linked C-glycopyranosides were obtained effectively by the radical addition reaction using V-70, an effective radical initiator under mild conditions.

(R)-5,6-Dihydro-5-phenyl-1,4-oxazin-2-one N-oxide {(R)-2} reacts with allyl alcohols 3a-c in the presence of magnesium bromide from the less hindered face via exo-mode to afford corresponding cycloadducts 4a-c with excellent stereoselection. Treatment of (R)-2 with three equivalents of racemic secondary allyl alcohols 3d-g under the same conditions causes partial kinetic resolution to give 4d-g as main products among eight possible stereoisomers. Cycloadduct ent-4a from (S)-2 and 3a was converted directly to g-lactone 6, which is known as the key synthetic intermediate of antibiotic clavalanine.

A novel sulfenylation method induced by aromatization of quinone mono-O,S-acetals is described. These sulfenylation reagents readily react with silyl enolethers or electron rich aromatic compounds to give sulfenylation products under mild conditions. In particular, O,S-acetal 2j, which possesses a pentafluorophenylthio function, is the most effective reagent from the standpoint of the adaptability for various substrates.