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Tris(2,2,2-trifluoroethyl)borate [B(OCH2CF3)3] was found to be a mild and general reagent for the formation of a variety of imines by condensation of amides or amines with carbonyl compounds. N-Sulfinyl, N-toluenesulfonyl, N-(dimethylamino)sulfamoyl, N-diphenylphosphinoyl, N-(α-methylbenzyl), and N-(4-methoxyphenyl) aldimines are all accessible using this reagent at room temperature. The reactions are operationally simple, and the products are obtained without special workup or isolation procedures.

Carbamoyl anions, generated from N,N-disubstituted formamides and lithium diisopropylamide, add with high diastereoselectivity to chiral N-sulfinyl aldimines and ketimines to provide α-amino amides. The methodology enables the direct introduction of a carbonyl group without the requirement of unmasking steps as with other nucleophiles. The products may be converted to α-amino esters or 1,2-diamines. Iterative application of the reaction enabled the stereoselective synthesis of a dipeptide. Spectroscopic and computational studies support an anion structure with η(2) coordination of lithium by the carbonyl group.

Air-stable P-chiral dihydrobenzooxaphosphole oxazoline ligands were designed and synthesized. When they were used in the iridium-catalyzed asymmetric hydrogenation of unfunctionalized 1-aryl-3,4-dihydronaphthalenes under one atmosphere pressure of H2, up to 99:1 e.r. was obtained. High enantioselectivities were also observed in the reduction of the exocyclic imine derivatives of 1-tetralones. [ABSTRACT FROM AUTHOR]

Is that SO? The title scaffolds have a highly active and properly differentiated SO bond for the efficient synthesis of enantiopure sulfinamides. The method is practical, green, and has the potential to provide an economical commercial process for the synthesis of bulky sulfinamides. [ABSTRACT FROM AUTHOR]