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236406-38-5

1-Piperidinecarboxylic acid, 4-(2-hydroxyethyl)-4-(hydroxyMethyl)-, 1,1-diMethylethyl ester synthesis

10synthesis methods
154348-08-0 Synthesis
tert-butyl 1-oxo-2-oxa-8-azaspiro[4.5]decane-8-carboxylate

154348-08-0
35 suppliers
$117.00/50mg

1-Piperidinecarboxylic acid, 4-(2-hydroxyethyl)-4-(hydroxyMethyl)-, 1,1-diMethylethyl ester

236406-38-5
16 suppliers
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Yield:236406-38-5 63%

Reaction Conditions:

Stage #1: 1,1-dimethylethyl 1-oxo-2-oxa-8-azaspiro[4,5]decane-8-carboxylatewith diisobutylaluminium hydride in dichloromethane at -78 - 0; for 5 h;
Stage #2: with water in dichloromethane at 0 - 20;

Steps:

42 DESCRIPTION 42; 1,1-Dimethylethyl 4-(2-Hydroxyethyl)-4-hydroxymethyl)-1-piperidinecarboxylate

Diisobutylaluminium hydride (1.0M in dichloromethane, 3.60 mL, 3.60 mmol) was added over 10 minutes to a stirred, cooled (-7820 C.) solution of 1,1-dimethylethyl 1-oxo-2-oxa-8-azaspiro[4.5]decane-8-carboxylate (Description 41, 400 mg, 1.57 mmol) in dichloromethane (4 mL) and the mixture stirred at -7820 C. for 3 hours, then at 020 C. for 2 hours. Water (1.6 mL) was added very slowly at 0° C. and the mixture was warmed to room temperature and stirred overnight. The mixture was filtered through Hyflo, washing with dichloromethane, and the solvent was evaporated under reduced pressure. The residue was purified by flash column chromatography on silica gel, eluting with ethyl acetate, to give the title compound (255 mg, 63%). m/z (ES+) 260 (M+1).

References:

US2003/225059,2003,A1 Location in patent:Page 27