Water → HCID 69666761, compound

Participants

Reaction Conditions

Reaction Steps

0.08 ml (0.2 mmol) of a 1.9M solution of n-butyllithium in hexane is added dropwise to a suspension of 76 mg (0.22 mmol) of chloromethyltriphenylphosphonium chloride in 1.7 ml of tetrahydrofuran cooled to 0° C. The solution is stirred for one hour and then 40 mg (0.18 mmol) of methyl 3-oxo-2,3,4,5-tetrahydro-1-benzoxepin-7-carboxylate, prepared according to example 4, in 2.5 ml of tetrahydrofuran are added at 0° C. via a hollow tube. The solution is stirred at ambient temperature for 1 h 30 and then water is added. After concentrating the solution, dichloromethane is added. The phases are separated and then the aqueous phase is extracted with dichloromethane. The combined organic phases are then washed using brine, are then dried and are finally concentrated under vacuum. The crude reaction product is then purified by chromatography on silica gel (ethyl acetate/heptane 10/90) to provide 11 mg (24%) of methyl 3-(chloromethylene)-2,3,4,5-tetrahydro-1-benzoxepin-7-carboxylate in the form of a mixture of two isomers in a Z/E ratio (70/30); 1H NMR (300 MHz, CDCl3): 2.6 (m, 2H), 2.99 (m, 2H), 3.9 (s, 3H), 4.79 (s, 2H), 6.07 (s, 1H), 7.04 (d, J=8.3 Hz, 1H), 7.84 (m, 2H).

Provenance & Evidence