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

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Reaction Steps

A solution of 4-{2-[3-(l-tert-butoxycarbonylmethyl-piperidin-4-yl)-1H-indazol-6-yl]-ethyl}-piperidine-1carboxylic acid tert-butyl ester (0.25 g, 0.475 mmol) in dry DMF (5 ml) was treated with sodium hydride (0.021 g, 0.523 mmol, 60% dispersion in oil) and the mixture was stirred at 23° under nitrogen for 30 min. A solution of 4-chlorobenzyl chloride (0.080 g, 0.497 mmol; Aldrich) in DMF (5 ml) was added and the mixture was stirred at 23° for 20 h. The solvent was removed in vacuo, the residue treated with water and extracted with dichloromethane (3×30 ml); the extracts were evaporated in vacuo to give an orange gum. Purification by flash chromatography on silica gel (Merck 9385), eluant ether: cyclohexane:triethylamine (50:50:2 to 100:0:2), gave the title compound as a colourless gum (0.107 g, 35%).

Provenance & Evidence