Nickel-catalyzed synthesis of oxazoles via C-S activation.

The synthesis of 2-substituted oxazoles is achieved via nickel-catalyzed cross-coupling reaction of 2-methylthio-oxazole and various organozinc reagents. An extension of this method is demonstrated with a chemoselective, one-pot synthesis of unsymmetrical 2,5-disubstituted oxazoles. This synthesis of 2- and 2,5-substituted oxazoles using this method provides great advantages over previous methods for these compounds and is highly complementary to current cyclodehydration strategies.

A Preparation of enantiomerically enriched axially chiral beta-diketimines: synthesis of (-)- and (+)-IAN amine.

The preparation of an enantiomerically enriched beta-diketimine composed of isoquinoline and 2-aminonaphthalene (IAN amine) is described, thereby offering new opportunities in the synthesis of nonracemic beta-diketimine- and pyridine-based chiral catalysts.

A practical, metal-free synthesis of 1H-indazoles.

The synthesis of 1H-indazoles is achieved from o-aminobenzoximes by the selective activation of the oxime in the presence of the amino group. The reaction occurs with a variety of substituted o-aminobenzoximes using a slight excess of methanesulfonyl chloride and triethylamine at 0-23 degrees C and is amenable to scale-up. The synthesis of 1H-indazoles under these conditions is extremely mild compared with previous synthetic approaches and affords the desired compounds in good to excellent yields.