Process for the preparation of 5(6)-thio substituted benzimidazoles
US4599428A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 21, 1984 |
| Grant date | Jul 8, 1986 |
| Priority date | — |
| Expiry date | Mar 21, 2004 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07D235/32
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
A process is disclosed for the preparation of a compound of the formula (XI) ##STR1## or a salt thereof, wherein R.sup.1 is hydrogen, halogen, C.sub.1 to C.sub.4 alkyl, C.sub.1 to C.sub.3 alkoxy, or trifluoromethyl; PA1 R.sup.5 is amino or C.sub.1 to C.sub.4 alkoxycarbonylamino; and PA1 R.sup.4" is C.sub.1 to C.sub.6 alkyl, C.sub.2 to C.sub.6 alkenyl, C.sub.2 to C.sub.6 alkynyl, cyclohexyl, benzyl, or 2-phenyl-ethyl, which comprises the steps of: PA2 (a) reacting a compound of the formula (VIII) ##STR2## or a salt thereof, with a basic nucleophilic compound to yield a salt of the formula (IX) ##STR3## wherein R.sup.4' is a lone pair of electrons, in which case an alkali metal or alkali earth metal cation forms a salt with the sulfur atom; and PA2 (b) reacting a salt of the formula (IX) with a compound of the formula (X) EQU R.sup.4' --Q wherein PA1 Q is hydroxyl, halogen, 1/2SO.sub.4, 1/3PO.sub.3, SO.sub.3 C.sub.6 H.sub.5, or SO.sub.3 C.sub.6 H.sub.4 CH.sub.3 to yield the desired product.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.