The Synthesis of Substituted Tricyclo[6.2.2.0^2,7]dodecanes from 2-Cyclohexenone¹

Formation of 2-(3‘-Oxocyclohexyl)-2-cyclohexen-1-one via Reduction of 2-Cyclohexen-1-one with Electrogenerated Nickel(I) Salen

“…In an investigation of the use of electrogenerated bases to promote Michael addition reactions, Baizer et al observed that dimerization of 2-cyclohexen-1-one to afford 2-(3‘-oxocyclohexyl)-2-cyclohexen-1-one ( 1 ) in a yield of 65% can be promoted via reduction of only 0.13% of the starting material to its radical-anion (the electrogenerated base) at a mercury cathode in dimethylformamide containing tetra- n -propylammonium tetrafluoroborate. Apparently, however, the identification of 1 was based solely on earlier work by Leonard and Musliner, who employed only one-dimensional 1 H NMR data to conclude that treatment of 2-cyclohexen-1-one with aqueous sodium hydroxide leads to 1 . In other electrochemical research, Tissot and co-workers found that direct reduction of 2-cyclohexen-1-one at a mercury cathode in acetonitrile containing tetra- n -butylammonium tetrafluoroborate along with 5% water gives rise to 3-(3‘-oxocyclohexyl)cyclohexanone in essentially quantitative yield.…”

Conversion of podocarpic acid to an 18-nor steroid

“…The ethereal solution was filtered through anhydrous sodium sulfate and evaporated in vacuo to yield a tan foam (54 mg, 69%), which crystallized from ether-hexane. Recrystallization from ether gave 5b as fine tan crystals: mp 174-178°( 16 mg, 20%) (red-brown color with methanolic ferric chloride); ymax 3550-3025, 1752 (sh), 1725, 1660, and 1600 cm-1; nmr 0.50-3.00 (24 H, m with strong s at 0.69 and 1.21), 3.64 (3 H, s, OCH3), and 7.50 (1 H, broad s, disappears on addition of D20, C=COH); Xmax 223 nm (c 4500), 267 (3500), and 295 (4200) shifted to 240 (4200), 271 (2200), and 367 (5300) in ethanol-0.01 N sodium hydroxide; ro/e (rel intensity) 356 (56), M+ 332 (100), M -28, 304 (11), M -28 -28, 301 (11), M -59, 273 (9), M -59 -28, 272 (7), M -60 -28, 244 (7), M -28 -28 -60, 221 (35), possiblv rings A and B with On, 189 (9), 221 -32, 161 (52), 221 -60, 136 (32), 135 (22), 134 (20), 123 (31), 121 (35), 109 (17), 107 (16), 82 (15), and 81 (16).…”