Simple catalysts that use atom-economical oxygen as the terminal oxidant to accomplish selective ortho–ortho, ortho–para, or para–para homo-couplings of phenols are described. In addition, chromium salen catalysts have been discovered as uniquely effective in the cross-coupling of different phenols with high chemo- and regioselectivity.

Saucy selection: The first catalytic, enantioselective Saucy–Marbet Claisen rearrangement has been achieved. Palladium(II) (R)‐binap or tBuphox catalysts L*Pd(SbF6)2 were employed to generate allenyl oxindoles or spirolactones bearing a quaternary center with up to 98 % ee.

In this paper, a strategy to obtain highly enantioselective catalysts for the Claisen rearrangement of allyloxy- and propargyloxy-indoles is outlined. Ultimately, copper BOX and palladium BINAP or PHOX catalysts were discovered as superior in catalyzing Claisen rearrangements of allyloxy- or proparyloxy-substituted indoles to generate oxindoles bearing allyl- or allenyl-substituted quaternary centers. This method proved to be tolerant of a broad range of functional groups. Tandem reactions of the silyl-allene products provide rapid access to a variety of spirocyclic oxindoles in one operation.

Palladium(II)‐Katalysatoren mit (R)‐Binap oder tBuphox als Liganden L* vermitteln die erste erfolgreiche katalytische enantioselektive Saucy‐Marbet‐Claisen‐Umlagerung. Dabei entstanden Allenyloxindole oder Spirolactone mit quartärem Zentrum mit bis zu 98 % ee.

Selective Oxidative Homo-and Cross-Coupling of Phenols with Aerobic Catalysts. -(LEE, Y. E.; CAO, T.; TORRUELLAS, C.; KOZLOWSKI*, M. C.; J. Am. Chem. Soc. 136 (2014) 19, 6782-6785, http://dx.

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Enantioselective Saucy-Marbet Claisen Rearrangement. -The rearrangement of alkynyl substrates allows the synthesis of allenyl oxindoles having a quarternary stereocenters. Tandem combination with lactone formation results in direct synthesis of spirooxoindoles. -(CAO, T.; DEITCH, J.; LINTON, E. C.; KOZLOWSKI*, M. C.; Angew. Chem., Int. Ed. 51 (2012) 10, 2448-2451, http://dx.