Synthesis of (21‐³H₃)‐pregnenolone

Abstract

353 3 SYNTHESIS OF( 21-H~)-PRECNENOLONE. V.V. K r i s P r a s a d and Steven 0. F r a n k l i n Department of O b s t e t r i c s and Gynecology, A s i m p l e procedure f o r t h e preparation of 21-3Hpregnenolone using pregnenolone as s t a r t i n g m a t e r i a l i e described. The procedure involved r e m o v a l of t h e C-21-methyl group of t h e s t e r o i d and t h e side-chain w a s reconstructed with 3H -CH3MgI i n two steps: a Grignard reaction followed by oxidation of t h e resulting alcohol. An o v e r a l l yield of 71% w a s achieved.Key words: 3H -Methyliodide, Pregnenolone, G r i g n a r d Reaction

The preparation of [pentane‐5,5,5‐3H3]‐abnormal‐cannabidiol

“…All the following manipulations were conducted on a vacuum line. A solution of [ 3 H 3 ]‐methylmagnesium iodide (1 mmol at 74.3 Ci/mmol) in diethyl ether (2 mL) was prepared using the procedure of Prasad and Franklin7; to this solution at ambient temperature, a solution of 9 (20 mg, 0.033 mmol) in anhydrous THF (1 mL) was added with stirring. The reaction was allowed to stir at ambient temperature for another 10 min and then lithium tetrachlorocuprate in THF (0.1 M; 0.025 mL) was added.…”