Hydroxylamine → 2-(1,2-Benzoxazol-3-yl)acetic acid

HRID 1591958

반응식

HRID 1591958 반응식
O[C:2]1[C:3](=[O:12])[O:4][C:5]2[C:10]([CH:11]=1)=[CH:9][CH:8]=[CH:7][CH:6]=2.[NH2:13][OH:14]>>[O:14]1[C:9]2[CH:8]=[CH:7][CH:6]=[CH:5][C:10]=2[C:11]([CH2:2][C:3]([OH:12])=[O:4])=[N:13]1

참가 물질

3

실험 절차

Hydroxycoumarin (5) is treated with hydroxylamine to obtain benzo[d]isoxazol-3-yl-acetic acid (6) which is brominated at the alpha position to give benzo[d]isoxazol-3-yl-bromoacetic acid (7) from which 3-bromomethyl-benzo[d]isoxazole (8) is obtained by decarboxylation. The development of this process is limited in that the starting intermediate (1) is not commercially available and therefore the preparation of zonisamide is very complex. In fact, Posner reaction for the preparation of acid (6) requires the use of metal sodium. Moreover, when metal sodium is used in alcoholic solution, besides acid (6) also remarkable amounts of O-hydroxy-acetophenone-oxime as by-product are obtained. Furthermore, the decarboxylation reaction to give compound (8) requires drastic conditions, namely the presence of a large excess of 50% sulfuric acid and reflux temperature, and the resulting product is thus difficult to be isolated.

출처 및 근거

ORD 기록
ord-86e1b310359547d7be420b9c89a23448
출처 데이터셋
uspto-grants-2007_11
특허 번호
US07291742B2

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