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Regioselective and enantioselective hydroxylation of propargylic C-H bonds are useful reactions but often lack appropriate catalysts. Here a green and efficient asymmetric hydroxylation of primary and secondary C–H bonds at propargylic positions has been established. A series of optically active propargylic alcohols were prepared with high regio- and enantioselectivity (up to 99% ee) under mild reaction conditions by using P450tol, while the C≡C bonds in the molecule remained unreacted. This protocol provides a green and practical method for constructing enantiomerically chiral propargylic alcohols. In addition, we also demonstrated that the biohydroxylation strategy was able to scaled up to 2.25 mmol scale with the production of chiral propargyl alcohol 2a at a yield of 196 mg with 96% ee, which's an important synthetic intermediate of antifungal drug Ravuconazole. [ABSTRACT FROM AUTHOR]

An efficient dearomative (3 + 2) cycloaddition of para-quinamines and 2-nitrobenzofurans has been developed. This reaction proceeds smoothly under mild conditions and affords a series of benzofuro[3,2-b]indol-3-one derivatives in good to excellent yields (up to 98%) with perfect diastereoselectivities (all cases > 20:1 dr). The scale-up synthesis and versatile derivatizations demonstrate the potential synthetic application of the protocol. A plausible reaction mechanism is also proposed to account for the observed reaction process. This work represents the first instance of the N-triggered dearomative (3 + 2) cycloaddition of 2-nitrobenzofurans. [ABSTRACT FROM AUTHOR]