Tetrahydrofuran → HCID 66959182, compound

Participants

Reaction Steps

Lithium diisopropylamide (0.0048 mol) 2.40 ml of a 2M solution (in heptane/THF/ethylbenzene) was added to a stirred solution of 1.5 g (0.0045 mol) of 2,3-diphenylpropionic acid (3R)-1-azabicyclo[2.2.2]oct-3-yl ester in 30 ml of THF at −70° C. under a N2 atmosphere. CH2O (gas) was bubbled into the reaction mixture via a steady stream of dry N2 during 10 min at −70° C. and then while the mixture was warmed at room temperature. The reaction was quenched by addition of saturated ammonium chloride solution (100 ml) and the resultant mixture was extracted twice with 100 ml of ethyl acetate. The organic layers were combined, dried over MgSO4 and evaporated to yield 1.9 g of an oil. This 1.9 g were combined with 3.28 g of a previous preparation and the product obtained (5.18 g) was purified by chromatography on silica gel eluting with chloroform/methanol/ammonia from 97.5:2.5:0.25 to 90:10:1. Appropriate fractions were combined and evaporated to obtain the two diastereomers: Intermediates I-22a and I-22b

Provenance & Evidence