Novel protection of 1,2-diol for trans-dihydroxycyclopentene ring construction by the C H insertion of alkylidene carbene: Formal total synthesis of (+)-trehazolin
The chiral vicinal diol was protected as 6-methylene-1,4-dioxepane to construct a cyclopentene ring by the CH insertion of alkylidene carbene. The removal of the protecting group was achieved in a few steps, affording the corresponding diol in a reasonable yield. Using these reactions, the known synthetic intermediate for (+)-trehazolin was synthesized from d-diethyl tartrate. In addition, a short