The first total synthesis of (+/-)-Celaphanol A was accomplished starting from alpha-cyclocitral and 3,4-dimethoxy benzyl chloride via a six-step process, in which the intramolecular cyclization of ketone 4 with BF3.-Et2O afforded an all-cis isomer intermediate for synthesis of aromatic tricyclic diterpenes.
Cis-fused products were obtained in high yield from the cyclisations of a series of 2-aryl-1-(2,4,4-trimethyl-1-cyclohexen-3-yl)-ethanones bearing electron donating groups with (BF3Et2O)-Et-. as catalyst.
The first total synthesis of (+/-)-abieta-8, 11, 13-trien-7beta-ol (7) was accomplished via a strategy of AC --> ABC, in which the reduction of the ketone 6 with LiAlH4 gave exclusively the title compound.
The first total synthesis of (+/-)-abieta-8,11,13-trien-7beta-ol (1) was accomplished, in which alpha-cyclocitral was used as the A ring synthon, and triphenylphosphonium chloride (9), which was obtained from m-bromobenzyl alcohol (4) via five steps, as the C ring synthon. The reduction of another natural organic compound (+/-)-abieta-8,11,13-trien-7-one (2) with LiAlH4 gave exclusively the title compound 1.
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