The dirhodium caprolactamate [Rh(2)(cap)(4)] catalyzed oxidation of secondary amines to imines by tert-butyl hydroperoxide (TBHP) occurs with high chemo- and regioselectivity.

Homochiral (R)- and (S)-3,4-methylenedioxymethamphetamine (MDMA) were prepared in six steps (each) from the chiral pool precursors d- l-alanine, respectively. The key step, copper-catalysed regioselective ring-opening of an N-tosylaziridine with aryl Grignard reagent, proceeded high yield complete regioselectivity. Elaboration was achieved preservation configurational integrity, affording R- S-...

Abstract The regioselectivity of the intramolecular cyclization bifunctional α-phenyl alkenes can be controlled simply by choice organic chromophore as photocatalyst. central photoredox catalytic reaction in both cases is a nucleophilic addition hydroxy function to olefin substrates. N,N-(4-Diisobutylaminophenyl)phenothiazine catalyzes exo-trig cyclizations, whereas 1,7-dicyanoperylene-3,4,9,10...

One-pot, four-component procedure for the synthesis of a small library of new chiral spiro- oxindolopyrrolidines with high regio-, diastereo- (>99:1 dr), and enantioselectivity (up to 80% ee) is described. In this process, the regio- and stereochemical 1,3-dipolar cycloaddition of azomethine ylides, which were generated insitu by the reaction of isatin derivatives and sarcosin,with optically ac...

Selective transformation of 2-propargylthio-6-methyl-pyrimidin-4(1H)On e (2) to 3,5-dimethyl-7H-thiazolo [3,2-a] pyrimidin-7-one (3) is performed under the conditionof base catalysis . For elucidation of structure, palladium catalyzed cyclization reaction of (2) was carried out and the structures of the products were assigned (5) and (6). These compounds underwent isomerization to (3) and (4...

The H(2)-evolving potential of [FeFe] hydrogenases is severely limited by the oxygen sensitivity of this class of enzymes. Recent experimental studies on hydrogenase from C. reinhardtii point to O(2)-induced structural changes in the [Fe(4)S(4)] subsite of the H cluster. Here, we investigate the mechanistic basis of this observation by means of density functional theory. Unexpectedly, we find t...

In situ modification of Grubbs' first-generation metathesis catalyst allows for a tandem enyne metathesis/hydrovinylation that is complementary to the regioselectivity of known ruthenium-catalyzed hydrovinylations.

The treatment of activated alkynes with catalytic amounts of Stryker’s reagent and tributylstannane resulted in hydrostannation. The reaction proceeds with high regioselectivity to produce α-stannated vinylstannanes exclusively.