Diarylmethanes asymmetric

Asymmetric diarylmethanes, hydrogenolytic behaviors, 29 229-270, 247-252 catalytic hydrogenolysis, 29 243-258 kinetics and scheme, 29 252-258 M0O3-AI2O3 catalyst, 29 259-269 relative reactivity, 29 255-257 schematic model, 29 254 Asymmetric hydrogenations, 42 490-491 Asymmetric synthesis, 25 82, 83 examples of, 25 82 Asymmetry factor, 42 123-124 Atom-by-species matrix, 32 302-303, 318-319 Atomic absorption, 27 317 Atomic catalytic activities of sites, 34 183 Atomic displacements, induced by adsorption, 21 212, 213 Atomic rate or reaction definition, 36 72-73 structure sensitivity and, 36 86-87 Atomic species, see also specific elements adsorbed... 

Such hydrogenolysis indicates that the following two parallel reactions occur and that their ratio will vary substantially with degree and location of methyl group in the catalytic hydrogenolysis of asymmetric diarylmethanes (Ar—CH2—Ar ) ... 

It is interesting to consider the factors affecting the product selectivity. Our experimental studies have examined precisely such phenomena. In this article we review the hydrogenolysis of asymmetric diarylmethanes based on our investigations. 

Initial research centered on the hydrogenolytic behavior of asymmetrically methyl-substituted diarylmethanes (hereafter abbreviated as asym DAMs) on C0O-M0O3-AI2O3 catalyst. 

HYDROGENOLYTIC BEHAVIORS OF ASYMMETRIC DIARYLMETHANES 237 TABLE I Continued)... 

D. The Kinetics and the Scheme of the Catalytic Hydrogenolysis of Asymmetric Diarylmethane... 

A second approach dealing with the asymmetric proto-nation of preformed carbanions was reported by Levacher and co-workers. ° The authors took advantage of the acidity of the diarylmethane position to perform a deproto-nation/asymmetric protonation sequence by the use of BuLi complexed with sparteine (Scheme 31.3). The use of... 

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