Journal of the American Chemical Society, Vol.127, No.15, 5596-5603, 2005
Crotylsilane reagents in the synthesis of complex polyketide natural products: Total synthesis of (+)-discodermolide
An efficient, highly convergent stereocontrolled synthesis of (+)-discodermolide has been achieved with 2.1% overall yield (27 steps longest linear sequence). The absolute stereochemistry of the C1 -C6 (112), C7-C14 (13), and C15-C24 (11) subunits was introduced using asymmetric crotylation methodology. Key elements of the synthesis include the use of hydrozirconation-cross-coupling methodology for the construction of C13-C14 (2)-olefin, acetate aldol reaction to construct the C6-C7 bond and install the C7 stereocenter with high levels of 1,5-anti stereoinduction, and the use of palladium-mediated sp(2)-sp(3) crosscoupling reaction to join the advanced fragments, which assembled the carbon framework of discodermolide.