Use of olefin templates in queued chemical transformations using late transition metal catalysis. Total synthesis of cis and trans bupleurynol via a single multireaction sequence.

1-Bromo-2-iodoethylene (9) was used as a central, pseudosymmetric building block for the fully convergent and modular synthesis of two related natural products, cis (1a) and trans (1b) bupleurynol. In doing so, a 9-step synthesis of 1a (reported previously) has been vastly truncated to one single operation by using queued cross-coupling reactions with Pd catalysis, negating the need for any protecting group chemistry.

Metal-catalyzed coupling reactions on an olefin template: the total synthesis of (13E,15E,18Z,20Z)-1-hydroxypentacosa- 13,15,18,20-tetraen-11-yn-4-one 1-acetate.

The naturally occurring ant venom (13E,15E,18Z,20Z)-1-hydroxypentacosa-13,15,18,20-tetraen-11-yn-4-one 1-acetate was synthesized stereospecifically using a series of metal-mediated cross-coupling reactions. The use of the difunctional olefin template (E)-1-chloro-2-iodoethylene as the central, pseudosymmetrical building block facilitated a fully convergent and, thus, efficient strategy to prepare this polyunsaturated natural product.