In homogeneous catalysis, the catalyst is in the same phase as the reactant. The number of collisions between reactants and catalyst is at a maximum.In a patent, 126456-43-7, name is (1S,2R)-1-Amino-2,3-dihydro-1H-inden-2-ol, introducing its new discovery. 126456-43-7
Stereodivergent SN2@P reactions of borane oxazaphospholidines: Experimental and theoretical studies
The stereodivergent ring-opening of 2-phenyl oxazaphospholidines with alkyl lithium reagents is reported. N-H oxazaphospholidines derived from both (+)-cis-1-amino-2-indanol and (-)-norephedrine provide inversion products in a highly stereoselective process. In contrast, N-Me oxazaphospholidines yield ring-opening products with retention of configuration at the P center, as previously reported by Juge and co-workers. As a result, from a single amino alcohol auxiliary, both enantiomers of key P-stereogenic intermediates could be synthesized. Theoretical studies of ring-opening with model oxazaphospholidines at the DFT level have elucidated the streochemical course of this process. N-H substrates react in a single step via preferential backside SN2@P substitution with inversion at phosphorus. N-methylated substrates react preferentially via a two-step frontside SN2@P, yielding a ring-opened product in which the nucleophilic methyl binds to P with retention of configuration. DFT calculations have shown that the BH3 unit is a potent directing group to which the methyl lithium reagent coordinates via Li in all the reactions studied.
Note that a catalyst decreases the activation energy for both the forward and the reverse reactions and hence accelerates both the forward and the reverse reactions.126456-43-7, you can also check out more blogs about126456-43-7
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Chiral nitrogen ligands in late transition metal-catalysed asymmetric synthesis¡ªI. Addressing the problem of ligand lability in rhodium-catalysed hydrosilations,
Nitrogen-Containing Ligands for Asymmetric Homogeneous and Heterogeneous Catalysis