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Sun reported an enantioselective construction of all‐carbon quaternary stereocenters from indoles and tertiary alcohol bearing o‐hydroxyphenyl moieties using SPINOL‐derived CPA 13d (Scheme 2.79) [166]. o‐Quinone methide intermediate was generated in situ.

Scheme 2.79. Construction of all‐carbon quaternary stereocenters from indoles and tertiary alcohol.

Source: Based on [166].

Sun reported the construction of tetraarylmethanes by way of in situ generated para‐quinone methide or extended iminium intermediates catalyzed by CPA 6l to afford triaryl(2‐pyrrolyl)methane (Scheme 2.80a) and diaryl(2‐indolyl)(2‐pyrrolyl)methane (Scheme 2.80b) with 83–99% ee and 83–97% ee, respectively [167]. The presence of 2‐alkoxy moiety on the phenyl moiety was critical for the excellent enantiocontrol.

Scheme 2.80. Construction of triarylpyrrolylmethanes (a) and diarylindolylpyrrolylmethanes (b).

Source: Based on [167].