2-Propynoic acid, 3-phenyl-, ethyl ester → ethyl 2-oxo-4-phenyl-2H-pyrimido[2,1-b]benzothiazole-8-acetate

HRID 34534

Reaction equation

HRID 34534 reaction equation
[NH2:1][C:2]1[S:3][C:4]2[CH:10]=[C:9]([CH2:11][C:12]([O:14][CH2:15][CH3:16])=[O:13])[CH:8]=[CH:7][C:5]=2[N:6]=1.[C:17]1([C:23]#[C:24][C:25](OCC)=[O:26])[CH:22]=[CH:21][CH:20]=[CH:19][CH:18]=1>>[O:26]=[C:25]1[CH:24]=[C:23]([C:17]2[CH:22]=[CH:21][CH:20]=[CH:19][CH:18]=2)[N:6]2[C:2]([S:3][C:4]3[CH:10]=[C:9]([CH2:11][C:12]([O:14][CH2:15][CH3:16])=[O:13])[CH:8]=[CH:7][C:5]=32)=[N:1]1

Participants

3

Reactant 2

HCID 915162-Propynoic acid, 3-phenyl-, ethyl esterHCID 821202(2-Amino-benzothiazol-6-yl)-acetic acid ethyl ester

Product 1

HCID 13477943ethyl 2-oxo-4-phenyl-2H-pyrimido[2,1-b]benzothiazole-8-acetateYield 26%

Conditions

Temperature
200 °C

Procedure

A stirred mixture of 5 g of ethyl 2-aminobenzothiazole-6-acetate and 6 g of ethyl phenylpropiolate was heated at 200° C. in an oil bath for 1 hour and the crude mixture was then purified on a column of 200 g of silica using CHCl3 as eluant. The product obtained was highly colored and was crystallized from CHCl3 and crystallized from ethanol to obtain 1.99 g (26% yield) of ethyl 2-oxo-4-phenyl-2H-pyrimido[2,1-b]benzothiazole-8-acetate as orange plates.

Workup

  1. customthe crude mixture was then purified on a column of 200 g of silica
  2. customThe product obtained
  3. customwas crystallized from CHCl3
  4. customcrystallized from ethanol

Sources & evidence

ORD record
ord-f4eb3194b1364147abc2863c106177f3
Source dataset
uspto-grants-1988_08
Patent number
US04762840

Linked notes

Loading…