Efavirenz is manufactured worldwide, and its asymmetric synthesis requires a complex organometallic approach, while an organocatalytic approach is far less efficient. The first highly enantioselective approach is disclosed for the synthesis of Efavirenz under nonmetal organocatalysis with up to 93% ee for the Merck intermediate and 91% ee for the Lonsa intermediate using novel alkynyl cinchona catalysts.

A facile synthetic route to monofluoromethyl substituted epoxides via the desymmetrization of 1,3‐difluoropropan‐2‐ols is reported. A silicon‐containing additive activates the inert C(sp3)−F bond in aliphatic fluorides to promote the intramolecular epoxidation under metal‐free reaction conditions. A phosphazene base, which acts as a catalyst, is indispensable for this silicon‐induced defluorinative cyclization.

We disclose the first asymmetric activation of a non‐activated aliphatic C−F bond in which a conceptually new desymmetrization of 1,3‐difluorides by silicon‐induced selective C−F bond scission is a key step. The combination of a cinchona alkaloid based chiral ammonium bifluoride catalyst and N,O‐bis(trimethylsilyl)acetoamide (BSA) as the silicon reagent enabled the efficient catalytic cycle of asymmetric Csp3−F bond cleavage under mild conditions with high enantioselectivities. The ortho effect of the aryl group at the prostereogenic center is remarkable. This concept was applied for the asymmetric synthesis of promising agrochemical compounds, 3,5‐diaryl‐5‐fluoromethyloxazolidin‐2‐ones bearing a quaternary carbon center.

A mild oxidation method for the conversion of aldoximes to carboxylic acids was developed mediated by hypervalent iodine reagents. This method covers a wide range of functionalized aldoximes and proceeds under mild conditions, utilizing PhI(OH)OTs as an oxidant.