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The initial phase of the synthesis entailed introduction of a synthetic equivalent of the spiro 0-lactone moiety onto 4 followed by functionalization of the f/wis-hydrindan skeleton in a stereo-controlled manner. Thus, the dienolate generated from 4 (3 equiv of NaH, DME, reflux) was reacted with diiodide 56 (1.5 equiv) at 60 C to provide spiro enone 67 (83%)(Scheme I). Stereo-selective cis-hydroxylation and protection as the acetonide then gave 7 (81% overall), possessing the desired trans-fused hydrindan skeleton. 8 9Selective reduction of the keto group followed by dehydration of the resulting alcohol provided olefin 8 (mp 106-107 C, 82% overall), which was transformed into acetate 10 (84% overall) via a two-step sequence:(1) reduction of 8 leading to alcohol 9 (mp 106-107 C);(2) acetylation of 9. Epoxidation of 10 with w-CPBA then proceeded stereoselectively to furnish the desired «-epoxide ll8, 9a (91%) as the …