Dimethylformamide → 2-Hydroxy-3-(2-nitrophenyl)propanoic acid

HRID 4735

반응식

HRID 4735 반응식
CN(C)C=O.S(Cl)(Cl)=O.[N+:10]([C:13]1[CH:18]=[CH:17][CH:16]=[CH:15][C:14]=1[CH2:19][C:20](=[O:24])[C:21]([OH:23])=[O:22])([O-:12])=[O:11]>>[OH:24][CH:20]([CH2:19][C:14]1[CH:15]=[CH:16][CH:17]=[CH:18][C:13]=1[N+:10]([O-:12])=[O:11])[C:21]([OH:23])=[O:22]

참가 물질

4

실험 절차

To magnetically stirred N,N-dimethylformamide (23 ml., 297.3 mmol) cooled in ice was slowly added dropwise thionyl chloride (139 ml., ca. 1.91 mol). A solution of (+)-α-hydroxy-2-nitrobenzenepropanoic acid [11.60 g., 54.9 mmol, [α]D25 +49.94° (c 2.465, 95% EtOH)], obtained from the chiral reduction of 2-nitro -α-oxobenzenepropanoic acid described in Example 1, in dichloromethane (133 ml.) was then added dropwise to the cold Vilsmeier reagent. The ice bath was removed and the solution, protected from moisture, was left at room temperature (25° C.) for 18 hours. The resulting yellow solution was evaporated to syrup. The syrup was dissolved in dichloromethane and the solution was poured cautiously onto stirred ice. The mixture was stirred for one hour during which time it warmed to room temperature. The organic phase was separated, washed (×3) with water and dried (MgSO4). Evaporation gave a syrup which was subjected to an oil pump vacuum for 0.5 hour. The syrup was dissolved in ether and 2,6-dimethylpiperidine was added to approximate neutrality (ca. pH 8 by pH paper). The crude titled compound (12.40 g., 66%) crystallized readily, m.p. 148°-153° C. Three crystallizations (with decolorization) from methanol-ether gave 6.01 g. (32% of pure product, m.p. 164°-167° C. dec., [α]D25 -41.49° (c 1.005, 95% EtOH).

출처 및 근거

ORD 기록
ord-4bb14ca94d854de98c85274ad779da40
출처 데이터셋
uspto-grants-1988_02
특허 번호
US04727183

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