Aluminium lithium hydride → N-(1-benzyl-4-piperidinyl)-2-hydroxymethyl-3-fluoroaniline

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Reaction Steps

To a solution of lithium aluminum hydride (0.9 g) in anhydrous tetrahydrofuran (160 ml) is added 2-(1-benzyl-4-piperidinylamino)-6-fluorobenzoic acid (8.0 g) and the mixture is refluxed for 1 hour. After cooling, the reaction solution is poured into ice-water and then extracted with dichloromethane. The solvent is concentrated and to the resulting residue is added diethyl ether/n-hexane. The precipitated crystal is collected by filtration to give N-(1-benzyl-4-piperidinyl)-2-hydroxymethyl-3-fluoroaniline (5.6 g) as light yellow powders, m.p.: 167°-170° C. Compounds of formula II are prepared as taught in European patent application EP 0 470514 A1, published Feb. 2, 1992. The carbostryril derivatives of formula II of the present invention can be prepared by various processes, for example, by the processes shown in the following reaction schemes. ##STR460## wherein R is the same RA as defined above or a group of the formula: ##STR461## wherein n and R3B are the same as defined above, and D is a group of the formula: --CH=CHR14' (R14' is a lower alkoxy, phenyl or a halogen atom), a group of the formula: ##STR462## (R9 and R10 are each a lower alkyl), or a group of the formula: --C=CH, and Y is hydrogen atom or a lower alkyl.

Provenance & Evidence