730240-92-3Relevant academic research and scientific papers
Synthesis of highly enantiomerically enriched amines by the diastereoselective addition of triorganozincates to N-(tert-butanesulfinyl)imines
Almansa, Raquel,Guijarro, David,Yus, Miguel
experimental part, p. 2484 - 2491 (2009/04/11)
The reaction of triorganozincates with (R)-N-(tert-butanesulfinyl) imines gives the expected α-branched sulfinamides in good to excellent yields with diastereomeric ratios of up to 98:2. The N-sulfinyl group of the products can be easily removed by acidic treatment, affording the corresponding chiral primary amines in enantiomeric excesses of up to 96%. The reactivity and the selectivity shown by the triorganozincates are different from the ones observed with the corresponding Grignard reagents, which allows, in several cases, the preparation of both enantiomers of an amine from the same imine substrate. When mixed triorganozincates are used, one can take advantage of the slow transfer rate of the methyl group to use it as a non-transferable one. Both aromatic and aliphatic aldimines, as well as activated ketimines, are good substrates for these addition reactions.
Lithiated carbamates: Chiral carbenoids for iterative homologation of boranes and boronic esters
Stymiest, Jake L.,Dutheuil, Guillaume,Mahmood, Adeem,Aggarwal, Varinder K.
, p. 7491 - 7494 (2008/09/17)
(Chemical Equation Presented) Take your pick: Either enantiomer of either diastereomer of substrates bearing adjacent stereogenic centers is accessible through reaction of an (R)- or (S)-lithiated carbamate with an (R)- or (S)-boronic ester (see scheme; pin = pinacolate, OCb = substituted carbamate).
Enantioselective synthesis of α,α-disubstituted amines from nitroalkenes
Leroux, Mary-Lorene,Le Gall, Thierry,Mioskowski, Charles
, p. 1817 - 1823 (2007/10/03)
Disubstituted nitroalkenes were converted into enantiomerically enriched amines (isolated as their hydrochloride salts) with enantiometric excesses of 88 to >95% in there steps: (a) highly stereoselective conjugate addition of the potassium salt of 4-phenyloxazolidin-2-one; (b) radical-mediated removal of the nitro group; (c) cleavage of the oxazolidinone.
