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The styryl dehydro-Diels–Alder reaction with a conjugated diyne is reported. While typical alkyne–styrene condensation requires elevated temperatures (>160 °C), the application of a conjugated diyne allowed for effective transformation under milder conditions (80 °C). The thermally stable triazole–gold (TA–Au) catalyst further improved the reaction yields (up to 95%), producing the desired alkynyl–naphthalene in a single step with molecular oxygen as the oxidant. Sequential alkyne activation resulted in various polyaromatic hydrocarbons (PAHs) in excellent yields, highlighting the efficiency of this new strategy for the preparation of PAHs with good functional group tolerance and structural diversity. 

A new class of stable four-coordinated benzotriazole-borane compounds was developed via gold-catalyzed alkyne hydroboration. The application of polymeric (BH 2 CN) n reagent gave the formation of cyano-amine-boranes (CAB) complexes with less basic N-heterocyclic amines and anilines. Various new CABs were investigated in catalytic hydroboration to synthesize N–B cycles. The 1,2,3-benzotriazoles were identified as the only feasible N-source, giving the four coordinated borane N–B cycles (BTAB) in excellent yields (up to 90%) with good functional group tolerability. This new class of polycyclic N–B compounds showed excellent stability toward acid, base, high temperature, and photo-irradiation. The facile synthesis, excellent stability, strong and tunable fluorescence emission make BTAB interesting new fluorescent probes for future chemical and biological applications. 

With the well‐documented chemical and biological applications, piperidine and pyridine are among the most important N‐heterocycles, and a new synthetic strategy, especially one with an alternative bond‐forming design, is of general interest. Using the gold‐catalyzed intermolecular condensation of amine and diyne‐ene, we report herein the first example of enantioselective 1,2‐dihydropyridine synthesis through a formal [3+2+1] fashion (up to 95 % yield, up to 99 % e.e.).

 

With the well‐documented chemical and biological applications, piperidine and pyridine are among the most important N‐heterocycles, and a new synthetic strategy, especially one with an alternative bond‐forming design, is of general interest. Using the gold‐catalyzed intermolecular condensation of amine and diyne‐ene, we report herein the first example of enantioselective 1,2‐dihydropyridine synthesis through a formal [3+2+1] fashion (up to 95 % yield, up to 99 % e.e.).

 

Herein, we reported an intermolecular asymmetric hydrative aldol reaction through vinyl‐gold intermediate under ambient conditions. This tandem alkyne hydration and sequential nucleophilic addition afforded a “base‐free” approach to β‐hydroxy amides with high efficiency (up to 95 % yields, >50 examples). Vinyl gold intermediate was applied as reactive nucleophile and Fe(acac)₃was used as the critical co‐catalyst to prevent undesired protodeauration, allowing this transformation to proceed under mild conditions with good functional group tolerance and excellent stereoselectivity (>20 : 1 d.r. and up to 99 % ee).

 

Herein, we reported an intermolecular asymmetric hydrative aldol reaction through vinyl‐gold intermediate under ambient conditions. This tandem alkyne hydration and sequential nucleophilic addition afforded a “base‐free” approach to β‐hydroxy amides with high efficiency (up to 95 % yields, >50 examples). Vinyl gold intermediate was applied as reactive nucleophile and Fe(acac)₃was used as the critical co‐catalyst to prevent undesired protodeauration, allowing this transformation to proceed under mild conditions with good functional group tolerance and excellent stereoselectivity (>20 : 1 d.r. and up to 99 % ee).