A PdCl2(MeCN)2/PPhCy2 catalyst couples oxazoles with diarylmethyl carbonates or pivalates to form the corresponding triarylmethanes in good yields. The catalysis involves successive secondary benzylic sp(3) C-O and heteroaromatic sp(2) C-H cleavages and provides an effective access to heteroarene-containing triarylmethanes from nonhalogenated and nonmetalated starting materials, which is complementary to precedented cross-coupling technologies with organic halides and organometallic reagents.

A Pd/(R)-H8 -BINAP-catalyzed asymmetric benzylic alkylation of active methylene compounds has been developed. The reaction proceeds without the use of an external base, and the starting racemic diarylmethyl carbonates are converted into the optically active coupling products which contain the benzylic chiral stereocenter by a dynamic kinetic asymmetric transformation (DYKAT). Additionally, with suitable carbonates bases, the same palladium catalysis allows the corresponding pivalates to be adopted in the same DYKAT process.

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