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Catalytic asymmetric ?-Iminol rearrangement: new chiral platforms.

ABSTRACT: A series of 19 different asymmetric catalysts were screened in an effort to identify the first chiral catalyst for the rearrangement of ?-hydroxy imines to ?-amino ketones involving a 1,2-carbon shift. Although aluminate complexes of VAPOL, VANOL, and 7,7'-(t)Bu2VANOL were quite effective catalysts giving up to 88% ee, the ne plus ultra catalyst for this reaction was found to be a zirconium complex of VANOL which gives 97 to >99% ee for the majority of the substrates examined. An X-ray diffraction study of the catalyst reveals that the zirconium exists as a homoleptic complex with three VANOL ligands and two protonated N-methyl imidazoles.

SUBMITTER: Zhang X

PROVIDER: S-EPMC4195388 | biostudies-literature | 2014 Oct

REPOSITORIES: biostudies-literature

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Catalytic asymmetric α-Iminol rearrangement: new chiral platforms.

Zhang Xin X Staples Richard J RJ Rheingold Arnold L AL Wulff William D WD

Journal of the American Chemical Society 20140923 40

A series of 19 different asymmetric catalysts were screened in an effort to identify the first chiral catalyst for the rearrangement of α-hydroxy imines to α-amino ketones involving a 1,2-carbon shift. Although aluminate complexes of VAPOL, VANOL, and 7,7'-(t)Bu2VANOL were quite effective catalysts giving up to 88% ee, the ne plus ultra catalyst for this reaction was found to be a zirconium complex of VANOL which gives 97 to >99% ee for the majority of the substrates examined. An X-ray diffracti ...[more]

PMID: 25247674

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