1,2-Difluorobenzene → HCID 12801622, compound

Participants

Reaction Conditions

Reaction Steps

A mixture of 6.3 g of 6-chloro-1'-methylspiro[indoline-3,4'-piperidine], Example 23b, 1.5 g of sodium hydride, 10 g of 0-difluorobenzene and 50 ml of dimethylsulfoxide is stirred at 60° C. under nitrogen for 30 minutes. Thereafter, the mixture is permitted to cool before adding ice-water. The biphasic mixture is extracted thrice with ether. The combined ether extracts are extracted with a large excess of dilute hydrochloric acid. The acidic extract is basified with concentrated ammonium hydroxide effecting a heavy oil. The oil is purified by passing through an alumina column, ether eluant, to provide a yellowish oil. The oil, in ether, is converted to its maleic acid salt which is recrystallized from an acetone-ether mixture providing off-white crystals, mp 166°-168° C. of 6-chloro-1-(2-fluorophenyl)-1'-methylspiro[indoline-3,4'-piperidine] maleate.

Provenance & Evidence