Process for preparing a ketimine
AssigneePfizer Inc.
InventorJames C. Spavins
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Abstract
An improved condensation process for preparing N-[4-(3,4-dichlorophenyl)-3,4-dihydro-1(2H)-naphthalenylidene]methanamine from 4-(3,4-dichlorophenyl)-3,4-dihydro-1(2H)-naphthalenone and methylamine is disclosed. The process involves the use of a hydratable molecular sieve having a pore size that is at least about three Angstrom units in diameter as the dehydrating agent (catalyst) in a reaction-inert aprotic organic solvent. The ketimine final product so produced is known to be useful as an intermediate leading to cis-(1S)(4S)-N-methyl-4-(3,4-dichlorophenyl)-1,2,3,4-tetrahydro-1-naphthal enamine (sertraline), which is an anti-depressant agent.
Claims12
A process for preparing N-[4-(3,4-dichlorophenyl)-3,4-dihydro-1(2H)-naphthalenylidene]methanamine, which comprises contacting 4-(3,4-dichlorophenyl)-3,4-dihydro-1(2H)-naphthalenone with methylamine in a reaction-inert aprotic organic solvent in the presence of a hydratable molecular sieve having a pore size that is at least about three Angstrom units in diameter as catalyst, whereby water is removed from the resultant reaction mixture until formation of the desired ketimine final product is substantially complete.
Dependencies are inferred from the claim text.