A catalytic enantioselective synthesis of chiral monosubstituted oxiranes
摘要:
A new catalytic enantioselective synthesis of monosubstituted oxiranes has been developed from achiral trichloromethyl ketones by (a) enantioselective carbonyl reduction, (b) selective bis-dechlorination and (c) base-induced ring closure of the resulting chlorohydrins.
Trichloromethyl ketones: asymmetric transfer hydrogenation and subsequent Jocic-type reactions with amines
作者:Michael S. Perryman、Matthew E. Harris、Jade L. Foster、Anushka Joshi、Guy J. Clarkson、David J. Fox
DOI:10.1039/c3cc46070c
日期:——
Amino-amides are important pharmaceutical building-blocks. The enantioselective reduction of trichloromethyl ketones using ruthenium transfer hydrogenation catalysts is reported. The products react in a range of Jocic-type reactions to give enantiomerically enriched amino-amides.
Solution-phase synthesis and evaluation of tetraproline chiral stationary phases
作者:Zhi Dai、Guozhong Ye、Charles U. Pittman、Tingyu Li
DOI:10.1002/chir.22001
日期:2012.4
solution‐phasesynthesis of multigram amounts of two 9‐fluorenylmethoxycarbonyl (Fmoc)‐protected tetraproline peptides. These tetraproline peptides were then attached to amino derivatized silica gel. The replacement of the Fmoc group with the trimethylacetyl group lead to two tetraprolinechiralstationaryphases (CSPs). A comparison of the chromatographic behavior of these two solution‐phase‐synthesized
Catalytic enantioselective synthesis of secondary alcohols using C2-symmetric diamino diol ligands
作者:Biao Jiang、Yan Feng、Jian-Feng Hang
DOI:10.1016/s0957-4166(01)00409-8
日期:2001.9
A newclass of diamino diols was evaluated as catalytic ligands in the enantioselective borane reduction of aromatic ketones and the enantioselective ethylation of arylaldehydes with diethylzinc. By variation of the substitution pattern on the ketone, e.e.s of up to 94% could be obtained by in situ borane reduction using 0.025 equiv. of the ligand at 35°C in THF. N,N,N′,N′-Tetramethyldiamino diol and
London Dispersion Interactions Rather than Steric Hindrance Determine the Enantioselectivity of the Corey–Bakshi–Shibata Reduction
作者:Christian Eschmann、Lijuan Song、Peter R. Schreiner
DOI:10.1002/anie.202012760
日期:2021.2.23
experimental studies for a series of modified CBS catalysts equipped with dispersion energy donors (DEDs) in the catalysts and the substrates. Our results demonstrate that attractive LD interactions between the catalyst and the substrate, rather than steric repulsion, determine the selectivity. As a key outcome of our study, we were able to improve the catalystdesign for some challenging CBS reductions.
Described herein are compounds, pesticidally acceptable salts thereof, and compositions thereof that are useful, for example, for pest management and for controlling pests. In certain embodiments provided are enantioenriched and/or enantiopure compounds and pesticidally acceptable salts thereof, and methods of making same. Methods of controlling pests with the compounds of the disclosure are also provided.