Facile synthetic routes to a chiral chloro‐substituted biphenyl‐2,2′‐diyl hydrogen phosphate and a chiral O,O‐biphenyl‐2,2′‐diyl phosphoramidothioate are described. The performance of these compounds as catalysts for the hydrophosphonylation of imines and the Friedel–Crafts alkylation of indole was investigated. In the latter reaction, the chloro‐substituted phosphoric acid derivative was found to rival the best Brønsted acid catalysts reported to date.

I. Materials. All compounds were purchased from Aldrich, Alfa Aesar, TCI America, Matrix Scientific, Strem, and/or Fisher. NMR solvents were purchased from Cambridge Isotope Laboratories, Inc. Chlorobenzene (Acros) was used as-received. The flash chromatography of all compounds was performed utilizing silica gel 60 (32-63 micron) purchased from Bodman Industries. II. Instrumentation. Nuclear magnetic resonance (NMR) spectra were obtained using either a Bruker AvanceIII-500 or Bruker 300 NMR spectrometer. Chemical shifts for protons are reported in parts per million downfield from tetramethylsilane and are referenced to residual protium in the NMR solvent (CHCl 3 : δ 7.26). Chemical shifts for carbon are reported in parts per million downfield from tetramethylsilane and were referenced to the carbon resonances of the solvent (CDCl 3 : δ 77.2). Data are represented as follows: chemical shift, integration, multiplicity (s = singlet, d = doublet, sep = septet, m = multiplet, br = broad), coupling constants in Hertz (Hz), and assignment. Mass spectrometric data were obtained at the Caltech Mass Spectrometry Facility. A Biotage ® Initiator microwave reactor was used for all microwave experiments.Microwave reactions were conducted in septum-sealed, glass vials equipped with magnetic stirbars; an external surface sensor was used to monitor reaction conditions.

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Efficient Microwave Method for the Oxidative Coupling of Phenols. -An efficient protocol for the oxidative coupling of phenols and naphthols is developed and compared with other oxidative coupling methodologies. -(GRANT-OVERTON, S.; BUSS, J. A.; SMITH, E. H.; GUTIERREZ, E. G.; MOORHEAD, E. J.; LIN, V. S.; WENZEL*, A. G.; Synth. Commun. 45 (2015) 3, 331-337, http://dx.