Triethylamine → {9-[(2R,3R,4R,5R)-3,4-bis{[tert-butyl(dimethyl)silyl]oxy}-5-(methoxymethyl)tetrahydro-2-furanyl]-6-[(2,2-diphenylethyl)amino]-9H-purin-2-yl}methyl methanesulfonate

Participants

Reaction Steps

Methanesulfonyl chloride (0.6 ml, 7.7 mmol) was slowly added to a stirred solution of {9-[(2R,3R,4R,5R)-3,4-bis{[tert-butyl(dimethyl)silyl]oxy}-5-(methoxymethyl)tetrahydro-2-furanyl]-6-[(2,2-diphenylethyl)amino]-9H-purin-2-yl}methanol (4.22 g, 5.87 mmol) (preparation 15) and triethylamine (1.2 ml, 8.62 mmol) in dichloromethane (50 ml) and the mixture stirred at room temperature for 30 minutes. Triethylamine (1 ml, 7.2 mmol) and methanesulfonyl chloride (0.5 ml, 6.4 mmol) were then added and stirring continued for a further 15 minutes. The solvent was removed under reduced pressure and the residue purified by column chromatography on silica gel eluting with a gradient system of ethyl acetate:pentane (1:3) changing to ethyl acetate:pentane (1:1) to afford the title compound as a gum (4.52 g). MS: 820 (MNa+).

Provenance & Evidence