HCID 54072221, compound → HCID 54175899, compound

Participants

Reaction Conditions

Reaction Steps

43 g (0.11 mol) of 4-oxopiperidinomethylene bisphosphonic acid ethyl ester was dissolved in 500 mt of dried tetrahydrofuran, and 250 ml (0.25 mol) of a methyl magnesium bromide solution in tetrahydrofuran (concentration: 1 mol/) was added thereto. The mixture was stirred at 25° C. for 2 hours, then subjected to post treatment and purified by column chromatography (SiO2, cyclohexane/CHCl3 =1/1) to give 30.7 g (68.5%) of 4-hydroxy-4-methylpiperidinomethylene bisphosphonic acid ethyl ester as an oily substance. To 15.8 g (39.5 mmol) of this ester, 7.6 g (47.2 mmol) of diethylaminosulfur trifluoride was added at -78° C. in CH2Cl2, and the mixture was stirred at room temperature for 5 hours. The reaction solution was purified by column chromatography (SiO2, hexane/isopropylether=5/1) to give 6.3 (40%) of the above identified compound.

Provenance & Evidence