Synthesis of [7′-14C]- and [7′-13C]-rotenone, and [4′-14C]- and [4′-13C]-rot-2′-enonic acid: 1,4-allylic hydrogenolysis showing substantial stereoselectivity

Abstract

C-Trimethylsilyloxy protection of the B/C-ring junction allows regenerative synthesis of (–)-rotenone isotopically labelled at the C-7′-methylene, without loss of chirality; 1,4-hydrogenolysis of (–)-rotenone labelled in this way proceeds stereoselectively with transference of 88% of the label to the 4′-E-methyl of (–)-rot-2′-enonic acid.