Processes and intermediates for preparing 2-fluorothiophene derivatives
US6043379A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 26, 1999 |
| Grant date | Mar 28, 2000 |
| Priority date | — |
| Expiry date | Jul 26, 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.