π-Facial Selectivities in Hydride Reductions of Hindered Endocyclic Iminium Ions
نویسندگان
چکیده
منابع مشابه
Contribution of cation-π interactions in iminium catalysis.
Ab initio calculations were carried out for a benzyl-substituted iminium cation derived from (E)-crotonaldehyde and a chiral imidazolidinone that was developed as an organocatalyst by MacMillan et al. At the MP2 level of theory it is predicted that the phenyl group is close to the iminium moiety in the most stable conformer, suggesting that the cation-π interaction contributes to the stabilizat...
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This paper describes the selective reductions with thioborane derivatives, zinc—modified cyanoborohydride, and the ate complex from diisobutylaluminum hydride and n-butyllithium. Reaction of carboxylic acids with 1,3,2-dithiaborinane in the presence of stannous chloride or boron trifluoride etherate in tetrahydrofuran gives 1,3-dithianes in high yields. The reaction of acids with thexylphenylth...
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The exomethylenes of 2,6-disubstituted bicyclo[3.3.1]nonan-9-ones 2 are readily isomerized over a palladium catalyst under an atmosphere of hydrogen to predominantly form the isomer 3 with C2 symmetry with very little formation of the analogous product with C(s) symmetry. A hydrogen source is essential to effect the rearrangement.
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ژورنال
عنوان ژورنال: The Journal of Organic Chemistry
سال: 2018
ISSN: 0022-3263,1520-6904
DOI: 10.1021/acs.joc.8b02603