- PSYCHOTROPIC HETEROBICYCLOALKYLPIPERAZINE DERIVATIVES
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A series of psychotropic heterobicycloalkylpiperazine derivatives having the structure STR1 wherein V is a 3-or 4-membered unsaturated chain, containing all carbon atoms when 4-membered, or when a 3-membered chain, V contains an oxygen or sulfur atom as one of the members; R is H or C 1-4 alkyl; W is CH, N, CH 2, or a chemical bond; X is CH, N, SO 2, or CO, with the proviso that both W and X cannot simultaneously be N; and Z is a heteroaromatic ring system. These compounds are useful antipsychotic and/or anxiolytic agents.
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- The Scope and Limitations of Carboxamide-Induced β-Directed Metalation of 2-Substituted Furan, Thiophene, and 1-Methylpyrrole Derivatives Application of the Method of Syntheses of 2,3-Disubstituted Thiophenes and Furans
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The effects of change of solvent, metalating agent, reaction time, and reaction temperature on the lithiation of N,N-diethylthiophene-2-carboxamide and of the N-tert-butyl-2-carboxamide derivatives of furan, thiophene, and 1-methylpyrrole are explored, and optimum conditions are established for ring β-directed metalation.The tertiary carboxamido group is less effective in this context than the secondary amide function and appears to be of limited value in these heteroaromatic systems.The high metalation levels achievable with the furan and thiophene secondary amides allow high-yielding syntheses (through reaction of the lithiated intermediates with a wide range of electrophiles) of otherwise inaccessible 2,3-disubstituted derivatives.The synthetical value of the methodology appears to be limited only by the forcing conditions required for amide hydrolysis.
- Carpenter, Andrew J.,Chadwick, Derek J.
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p. 4362 - 4368
(2007/10/02)
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- Regioselective α-and β-Metallations of Thiophene Derivatives Bearing the 4,4-Dimethyloxazolin-2-yl Group. Application of the Method to Syntheses of 2,3- and 2,5-Disubstituted Thiophene Derivatives
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The effects of change of solvent, metallating agent, reaction time and temperature, and of the presence or absence of agents capable of complex formation with either the lithium cation or the oxazoline moiety, on the lithiation of 4,4-dimethyl-2-(2-thienyl)oxazoline are explored.Conditions are thereby established for high-yielding syntheses of the 3- and 5-lithio-intermediates and for control of regioselectivity of metallation.The nucleophilicity of 3-lithio-intermediate is profoundly solvent dependent, and appropriate conditions for reaction of both 3- and 5-lithiated species with a wide variety of electrophiles are presented.Syntheses of a range of 2,3- and 2,5-disubstituted thiophene derivatives have thereby been achieved, utilising, in addition, a new method for the transformation of oxazolino into carboxy functionality.The balance between basicity and nucleophilicity of the 3-lithio-intermediate in its reaction with - and -acetone is shown to be sensitive to isotope effects.
- Carpenter, Andrew J.,Chadwick, Derek J.
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p. 173 - 182
(2007/10/02)
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