New diphenyl diselenides -substituted by an O(S,Se)-caranyl skeleton - synthesis and application in asymmetric reactions

An efficient methodology for the synthesis of diphenyl diselenides o -substituted by O(S,Se)-caranyl moieties has been presented. 4-Caranyl and 4-isocaranyl groups have been connected to the phenyl ring by an oxygen, sulfur or selenium atom. The influence of the selenium-heteroatom interactions on the diastereoselectivity of the methoxyselenenylation of styrene has been evaluated. The best result was obtained for diselenide with an O-caranyl group substituted in the ortho -position. X-ray crystal structure of this compound was determined and the observed intramolecular interactions were discussed. Additionally diselenides bearing a sulfur atom were transformed to the corresponding methyl o -(S-caranyl) and o -(S-isocaranyl)-substituted phenyl selenides, and were tested as catalysts in the Tsuji-Trost allylic alkylation and Henry reaction. A convenient methodology for the synthesis of optically active diselenides and selenides functionalized with terpenyl moieties and their applications in the selenenylation of alkenes, and Tsuji-Trost and Henry reactions are presented.