Efficient amide-directed catalytic asymmetric hydroboration

Journal of the American Chemical Society

Volumn 130, Issue 12, 2008, Pages 3734-3735

  Smith, Sean M ^a   Thacker, Nathan C ^a   Takacs, James M ^a  

^a UNIVERSITY OF NEBRASKA LINCOLN   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

AMIDE;

ARTICLE; ASYMMETRIC CATALYSIS; CATALYST; CHEMICAL REACTION; CHEMICAL STRUCTURE; CHIRALITY; ENANTIOSELECTIVITY; HYDROBORATION; REACTION ANALYSIS; STRUCTURE ANALYSIS;

AMIDES; BORANES; CATALYSIS; KETONES; LIGANDS; MOLECULAR STRUCTURE; ORGANOMETALLIC COMPOUNDS; RHODIUM; STEREOISOMERISM;

EID: 41149165685     PISSN: 00027863     EISSN: None     Source Type: Journal    
DOI: 10.1021/ja710492q     Document Type: Article

References (24)

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21. It is interesting to note that while both the (E)- and (Z)-isomers of 1 react to completion under the optimized reaction conditions (40°C, 2 h), their reaction rates differ significantly. At lower temperature (25°C, 1 mol% catalyst loading) (Z)-1 reacts 3-4 times faster than (E)-1 using the BINOL-derived phosphoramidite 4 as the chiral ligand. In contrast, (E)-1 reacts 2-3 times faster than (Z)-1 using the TADDOL-derived phosphite 5b (25°C, 1 mol% catalyst loading).
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