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3-(Hetero)arylmethyl derivatives of imidazo[1,2-a]pyridine have been synthesized by a novel one-pot method consisting of the Sonogashira coupling of tert-butyl prop-2-yn-1-yl(pyridin-2-yl)carbamate with different substituted (hetero)aryl bromides and cyclization of the in situ obtained intermediate substituted (hetero)aryl acetylene derivatives.

We report the deprotonation of a chiral nitrile and reaction of the resulting chiral organometallic species with a variety of electrophiles to give highly enantiomerically enriched 2-substituted nitrile products. The nitrile was treated with TMPMgCl and the resulting anion, an asymmetric alpha cyano Grignard species, was found to be configurationally stable at low temperature for a short time (half-life several minutes at −104 °C).

Chiral AlIII salen complexes were synthesized and used as catalysts for the asymmetric hydrocyanation of nitroolefins using 4-phenylpyridine N-oxide as an additive and trimethylsilyl cyanide (TMSCN) as a source of cyanide. An excellent yield of β-nitronitrile (87 %) and enantioselectivity (90 %) were achieved if (2-nitrovinyl)cyclohexane was used as a substrate at −15 °C in 16 h. To understand the interaction of the AlIII salen complex and additive, NMR and IR spectroscopic studies revealed that 4-phenylpyridine N-oxide acts both as an axial ligand and helps to activate the cyanide source TMSCN, which thereby increases the reactivity. A catalytic cycle was proposed based on the spectroscopic studies.

Several chiral oxazoline-based organocatalysts are prepared and applied in the asymmetric allylation reaction of aldehydes with allyltrichlorosilane whereas, best results are achieved using OXA as catalyst shown here.