Alkanethiolation process
US5902906A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 1, 1997 |
| Grant date | May 11, 1999 |
| Priority date | — |
| Expiry date | May 1, 2017 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07C319/14
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
A mixture formed from one or more alkyl disulfides, benzene, and at least about 1.5 equivalents of Lewis acid catalyst is heated to form alkanethiobenzene. Reaction in a mixture formed from excess benzene, dimethyldisulfide (DMDS) and AlCl.sub.3 in which the mole ratio of AlCl.sub.3 to DMDS was 2:1 was complete in 2 hours and afforded 98% conversion and 93% yield of thioanisole. In contrast, the same reaction when attempted using a 1:1 mole ratio of AlCl.sub.3 to DMDS after 6 hours achieved only 66% conversion and a thioanisole yield of only 35%. So far as is known, this is the first example of a highly efficient electrophilic aromatic substitution of the inactivated benzene ring by an alkanethio group.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.