Oxalyl chloride → (+/-)-3-(3-Cyclopentyloxy-4-methoxyphenyl)sulfanyl-7-phenylheptanohydroxamic acid

Beteiligte Stoffe

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A stirred solution of (±)-3-(3-cyclopentyloxy-4-methoxyphenyl)sulfanyl-7-phenylheptanoic acid (0.40 g, Example 4) in a mixture of dimethylformamide (0.07 ml) and dichloromethane (20 ml) was treated dropwise with a solution of oxalyl chloride in dichloromethane (1.17 ml, 2.0 M). After stirring at room temperature for a further 30 minutes the mixture was treated dropwise with O-(trimethylsilyl)hydroxylamine (0.57 ml). The resulting white suspension was stirred for 10 minutes then partitioned between hydrochloric acid (50 ml, 1N) and ethyl acetate (50 ml). The aqueous layer was extracted twice with ethyl acetate (50 ml). The combined organic phases were washed with water (50 ml), then with brine (50 ml), then dried over magnesium sulphate and then evaporated to give the title compound (0.26 g) as a white foam. NMR (CDCl3): δ1.60 (m,8H), 1.86 (m,6H), 2.35 (br d,2H), 2.60 (br t,2H), 3.30 (m,1H), 3.80 (s,3H), 3.73 (m,1H), 6.76 (d,1H), 6.95 (d,2H), 7.10-7.30 (m,5H). Mass spectrum (FAB): m/z 444 (M+H)+.

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