Phosphorus pentachloride → 2,7-Dichlorobenzo[d]oxazole

HRID 1632486Notes

Reaction equation

HRID 1632486 reaction equation
[Cl:1][C:2]1[C:10]2[O:9][C:8](S)=[N:7][C:6]=2[CH:5]=[CH:4][CH:3]=1.P(Cl)(Cl)(Cl)(Cl)[Cl:13]>>[Cl:13][C:8]1[O:9][C:10]2[C:2]([Cl:1])=[CH:3][CH:4]=[CH:5][C:6]=2[N:7]=1

Participants

3

Reactant 2

HCID 24819Phosphorus pentachlorideHCID 178527783HCID 178527783, compound

Product 1

HCID 204431272,7-Dichlorobenzo[d]oxazole

Procedure

A mixture of 7-chloro-2-mercaptobenzoxazole (14.8 g.) and phosphorus pentachloride (29.2 g.) was heated at 160°-170° under reflux for 3 hours. The flask was fitted with a distilling head and the product was distilled in vacuo. The first two fractions were unreacted phosphorus chloride. Afterwards, the product distilled to give 2,7-dichlorobenzoxazole. This compound was reacted with hydrazine using the method described in procedure (a) of Example 1 and then reacted with acrylonitrile using procedure (c) of Example 1 to give 3-[1-(7-chloro-2-benzoxazolyl)hydrazino]propanenitrile, m.p. 114°-115° C.

Workup

  1. temperaturewas heated at 160°-170°
  2. temperatureunder reflux for 3 hours
  3. customThe flask was fitted with a distilling head
  4. distillationthe product was distilled in vacuo
  5. distillationAfterwards, the product distilled

Sources & evidence

ORD record
ord-e1e70fdf250140cdb1743ae123e6c2b9
Source dataset
uspto-grants-1984_10
Patent number
US04476137

Reaction notes

Loading…