A substrate-controlled synthesis of (+)-herboxidiene from two lactate-derived chiral ketones is described. Remarkably, most of the carbon backbone was constructed through highly stereoselective titanium-mediated aldol reactions and an Ireland–Claisen rearrangement. Furthermore, an oxa-Michael cyclization and a high-yield Suzuki coupling were used to assemble the pyran ring and the diene moiety respectively
作者:Alejandro Gómez-Palomino、Miquel Pellicena、Katrina Krämer、Pedro Romea、Fèlix Urpí、Gabriel Aullón、José M. Padrón
DOI:10.1039/c7ob00072c
日期:——
A total synthesis of (+)-herboxidiene/GEX 1A has been accomplished from (R)- and (S)-lactate esters in a highly efficient manner. Key steps of the synthesis involve substrate-controlled titanium-mediated aldol reactions from chiral lactate-derived ethyl ketones, an oxa-Michael cyclization, an Ireland–Claisen rearrangement, and a Suzuki coupling. Furthermore, computational studies of the oxa-Michael