Patent · US Expired

Processes and intermediates for preparing 2-fluorothiophene derivatives

US6096901A · kind A · utility

2Cited by
5References
3Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 30, 1999
Grant dateAug 1, 2000
Priority date
Expiry dateNov 30, 2019

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC07D333/38
  • WIPO fieldOrganic fine chemistry
  • WIPO sectorChemistry

Abstract

A process for the preparation of the compound of the formula: ##STR1## wherein R.sup.1 is OH, which comprises the steps of a) treating the compound of the formula: ##STR2## with an inorganic fluoride, of the formula M.sup.2 F wherein M.sup.2 is an alkali metal cation, at an elevated temperature in the presence of a compound of the formula R.sup.4 P.sup.+ Z.sup.- and a compound of the formula R.sup.5 vic (COW).sub.2 wherein R.sup.4 and R.sup.5 are each selected from optionally substituted (C.sub.6 -C.sub.10) aryl and optionally substituted (C.sub.1 -C.sub.6) alkyl, and W is halo; to form the compound of the formula: ##STR3## and b) I) treating the compound of the formula IV with an aqueous solution of a base, of the formula MOH, wherein M is an alkali metal cation, and PA2 ii) treating the product of step i) with a mineral acid. A compound of the formula: ##STR4## wherein R.sup.1 is selected from the group consisting of, halo, R.sup.7 O, R.sup.7 COO and N(R.sup.8).sub.2 wherein R.sup.7 is (C.sub.1 -C.sub.6)alkyl or (C.sub.6 -C.sub.10)aryl and each R.sup.8 is selected from hydrogen and R.sup.7 with the proviso that R.sup.7 is not methyl when R.sup.1 is R.sup.7 O.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.