تفاعل #6124

ord-826a99c45042499d9978bfa9b6772ca8

معادلة التفاعل

Br
hydrobromic acid
CC(=O)OC1SC[C@@H](OC(C)=O)[C@H](OC(C)=O)[C@H]1OC(C)=O
1,2,3,4-tetra-O-acetyl-5-thio-D-xylopyranose
→
CC(=O)O[C@@H]1[C@@H](OC(C)=O)[C@H](OC(C)=O)CS[C@H]1Br
expected product
المردود 39.0%
CC(=O)O[C@@H]1[C@@H](OC(C)=O)[C@H](OC(C)=O)CS[C@H]1Br
2,3,4-tri-O-acetyl-5-thio-β-D-xylopyranosyl bromide
المردود 39.0%

المتفاعلات

Br
hydrobromic acid
CC(=O)OC1SC[C@@H](OC(C)=O)[C@H](OC(C)=O)[C@H]1OC(C)=O
1,2,3,4-tetra-O-acetyl-5-thio-D-xylopyranose
—
solution

الكواشف

لا شيء

المذيبات

CC(=O)O
acetic acid
CC(Cl)Cl
dichloroethane

ظروف التفاعل

الظروف التفصيلية
See reaction.notes.procedure_details.

المعالجة

  1. 1
    غسيلwashed with a solution of sodium bicarbonate
  2. 2
    تجفيفdried over sodium sulfate (Na2SO4)
  3. 3
    أخرىthe solvent is evaporated off to dryness under reduced pressure

الإجراء التجريبي

3.50 ml of a 30% solution of hydrobromic acid in glacial acetic acid are added at 10° C. to a solution of 2.10 g (6.3.10-3 mol) of 1,2,3,4-tetra-O-acetyl-5-thio-D-xylopyranose in 10 cm3 of dichloroethane. After 2 to 3 h, the reaction medium is hydrolyzed, washed with a solution of sodium bicarbonate and dried over sodium sulfate (Na2SO4) and the solvent is evaporated off to dryness under reduced pressure. 0.87 g (yield: 39%) of the expected product is obtained after precipitation in ether.

المصدر

DOI: 10.6084/m9.figshare.5104873.v1براءة الاختراع: US05246961uspto-grants-1993_09