4-Toluenesulfonyl chloride → 10-[(4-methylphenyl)sulfonyl]-10H-pyrazolo[1',5':1,2]imidazo[4,5-c]quinoline

Participants

Reaction Steps

A solution of 10H-pyrazolo[1′,5′:1,2]imidazo[4,5-c]quinoline (1.00 g, 4.80 mmol) in tetrahydrofuran (24 mL), under a nitrogen atmosphere, was chilled in an ice-water bath. The solution was treated with NaH (0.29 g, 7.20 mmol, 60%) in small portions over 2 min. After 10 min, the mixture was treated with p-toluenesulfonyl chloride (1.01 g, 5.28 mmol), and allowed to come to ambient temperature. After 1.5 h the reaction was quenched with slow addition of water (5 mL). The reaction mixture was concentrated under reduced pressure to yield a brown solid. The solid was purified by prep. HPLC (100 g silica gel eluted with 1-10% CMA in chloroform) to give a tan foam. The foam was dissolved in methyl tert-butyl ether (25 mL) and filtered through filter paper. The filtrate was concentrated under reduced pressure to yield 0.49 g of 10-[(4-methylphenyl)sulfonyl]-10H-pyrazolo[1′,5′:1,2]imidazo[4,5-c]quinoline as a tan solid.

Provenance & Evidence