1-Chloro-4-(chloromethyl)benzene → 4-{2-[3-(1-tert-Butoxycarbonylmethyl-piperidin-4-yl)-1-(4-chloro-benzyl)-1H-indazol-6-yl]-(E)-vinyl}-piperidine-1-carboxylic acid tert-butyl ester

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Reaction Steps

A solution of 4-{2-[3-(1-tert-butoxycarbonylmethyl-piperidin-4-yl)-1H-indazol-6-yl]-(E)-vinyl}-piperidine-1-carboxylic acid tert-butyl ester (0.29 g, 0.553 mmol) in dry DMF (5 ml) was stirred under nitrogen and treated with sodium hydride (0.024 g, 0.608 mmol, 60% dispersion in oil). The mixture was stirred for 0.5 h and a solution of 4-chlorobenzyl chloride (0.090 g, 0.559 mmol; Aldrich) in DMF (5 ml) was added). The mixture was stirred at 23° for 16 h, evaporated in vacuo, treated with water (10 ml) and extracted with dichloromethane (3×20 ml). The extracts were evaporated in vacuo and purified by flash chromatography on silica gel (Merck 9385), eluant ether:cyclohexane:triethylamine (50:50:2 to 100:0:2), to give the title compound as a colourless gum (0.157 g, 44%).

Provenance & Evidence