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Volumn , Issue 19, 2008, Pages 2913-2937

Stereoselective synthesis of saturated heterocycles via palladium-catalyzed alkene carboetherification and carboamination reactions

Author keywords

Alkenes; Catalysis; Heterocycles; Palladium; Stereoselective synthesis

Indexed keywords

ALKENE; ALKENYL GROUP; IMIDAZOLIDINE DERIVATIVE; ISOXAZOLIDINE DERIVATIVE; PALLADIUM; PIPERAZINE DERIVATIVE; POLYCYCLIC AROMATIC HYDROCARBON DERIVATIVE; PYRROLIDINE DERIVATIVE; TETRAHYDROFURAN DERIVATIVE;

EID: 57649136407     PISSN: 09365214     EISSN: None     Source Type: Journal    
DOI: 10.1055/s-0028-1087339     Document Type: Review
Times cited : (212)

References (217)
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    • A small amount of a regioisomer analogous to 18 was also formed in this reaction.
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    • 8-Pd(II) complexes generally occur via an associative mechanism, see: (a) See also ref. 29a
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    • DEPBT = 3-(diethoxyphosphoryloxy)-1,2,3-benzotriazin-4(3H)-one. The use of other reagents (e.g., DCC/HOBt or CDI) resulted in partial epimerization to afford products with ca. 85-90% ee, see: Li, H.; Jiang, X.; Ye, Y.-h.; Fan, C.; Romoff, T.; Goodman, M. Org. Lett. 1999, 1, 91.
    • DEPBT = 3-(diethoxyphosphoryloxy)-1,2,3-benzotriazin-4(3H)-one. The use of other reagents (e.g., DCC/HOBt or CDI) resulted in partial epimerization to afford products with ca. 85-90% ee, see: Li, H.; Jiang, X.; Ye, Y.-h.; Fan, C.; Romoff, T.; Goodman, M. Org. Lett. 1999, 1, 91.
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    • Surprisingly, the stereochemical outcome of the piperazine-forming reactions is opposite to that predicted by the allylic strain model, similar to that shown in Scheme 11. Our current working hypothesis suggests that the piperazine-forming reactions proceed through a transition state in which the N-aryl group is rotated to minimize allylic strain interactions, and the structure around the cyclizing nitrogen atom is pyramidal. Investigations into this hypothesis are currently underway.
    • Surprisingly, the stereochemical outcome of the piperazine-forming reactions is opposite to that predicted by the allylic strain model, similar to that shown in Scheme 11. Our current working hypothesis suggests that the piperazine-forming reactions proceed through a transition state in which the N-aryl group is rotated to minimize allylic strain interactions, and the structure around the cyclizing nitrogen atom is pyramidal. Investigations into this hypothesis are currently underway.


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