Ethyl diazoacetate → HCID 21929636, compound

Participants

Reaction Conditions

Reaction Steps

0.9 cm3 of ethyl diazoacetate is added, dropwise, to a solution, cooled to −78° C., of 2 g of 4,4-bis(4-methoxyphenyl)cyclohex-2-enone in 50 cm3 of tetrahydrofuran, followed by slow addition of 13 cm3 of a lithium diisopropylamide solution prepared beforehand from 6.5 cm3 of 1.6 M n-butyllithium in hexane and 1.46 cm3 of diisopropylamine in solution in 15 cm3 of tetrahydrofuran. After stirring the reaction mixture at a temperature in the region of −70° C. for 3 hours, 1.2 cm3 of glacial acetic acid are added and the temperature is allowed to rise to the region of 20° C. 250 cm3 of ethyl ether are then added and the resultant mixture is then washed with twice 200 cm3 of distilled water and then dried over sodium sulphate and concentrated to dryness under reduced pressure. The residue is dissolved in 65 cm3 of toluene and then heated at a temperature in the region of 110° C. for 1.5 hours, followed by concentrating to dryness under reduced pressure. The residue obtained is purified by flash chromatography on a silica gel (35–70 μm), eluting with a cyclohexane/ethyl acetate (70/30) mixture to give 0.48 g of ethyl 6,6-bis(4-methoxyphenyl)-6,7-dihydro-1H-indazole-3-carboxylate in the form of a yellow foam, the characteristics of which are as follows:

Provenance & Evidence