1-(substituted benzyl)-3-(substituted aryl)-condensed pyrazole derivatives and processes of making the same
US5574168A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 3, 1994 |
| Grant date | Nov 12, 1996 |
| Priority date | — |
| Expiry date | May 3, 2014 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07D491/04
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
The invention pertains to a process for preparing (1-substituted benzyl)-3-(hydroxy-carbonyl aryl) condensed pyrazoles or (1-substituted benzyl)-3-(hydroxymethyl aryl) condensed pyrazoles comprising the steps of: (a) reacting compound I and compound II, or compound III and compound IV, to produce compound V, which is a substituted aryl ketone, as follows: ##STR1## wherein Ar.sub.2 and At.sub.3 can be, independently, ##STR2## R.sub.1 is H, C.sub.1-3 alkyl, or X (halogen), R.sub.3 is H, C.sub.1-3 alkyl, X (halogen), or --OR radical, and R is H or C.sub.1-3 alkyl; the process comprising the following steps of: R.sub.2 represents CH.sub.2 OR, H, COOR, C.sub.1-3 alkyl, or X (halogen); (b) reacting the compound V with a hydrazine compound to form a hydrazone compound; (c) reacting the hydrazone compound compound with trifluoride etherate (BF.sub.3 .cndot.Et.sub.2 O) to form a 1-(substituted benzyl) 3-(substituted aryl) condensed pyraxzole, which is represented by the following formula of ##STR3## Compound X can be further hydrolyzed or reduced to form corresponding carboxylic acids or alcohols.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.