Gold-complexes Or Non-metal Catalyzed Functionalization Of Sp~3C-H Bonds And Unsaturated Hydrocarbons

The development of green, efficient catalysts is of both economic and environmental significance. We are interested in developing green and efficient methods for the direct functionalization of sp3C-H bonds and alkenes. In this thesis, gold(Ⅲ)-complexes were synthesized, and used as the photocatalysts for the functionalization of sp3C-H bonds. Metal-free, highly efficient functionalization of sp3C-H bonds and unsaturated hydrocarbons has also been developed. The research work of this thesis includes:1. Visible-light-induced aerobic oxidative C-C coupling from C-H bonds catalyzed by a gold(Ⅲ)-complexVisible-light-induced, highly efficient gold(Ⅲ)-complex catalyzed aerobic oxidative a-C-H functionalization of amines has been developed. The tertiary amines can be directly coupled with various methyl ketones using air as a sustainable oxidant. Gold(Ⅲ)-complex ld displayed high photocatalytic activity in the oxidative coupling reaction high-lighting the richness of gold(Ⅲ) photochemistry.2. Visible-light-induced, gold-catalyzed oxidative phosphonation of sp3C-H bondsThe C-P bonds are ubiquitous in natural compounds. Direct phosphonation of C-H bonds is one of the most exciting strategies to synthesize phosphorus-containing molecules. We developed a visible-light-induced gold-catalyzed oxidative phosphonation of sp3C-H bonds with various diarylphosphine oxides and dialkyl phosphites using air as oxidant under mild reaction conditions.3. Metal-free, highly efficient organocatalytic amination of benzylic C-H bondsWe have reported a novel n-Bu4NI catalyzed operationally simple method for the oxidative coupling of benzylic C-H substrates with unmodified amines. Various amination products were obtained with good to excellent yields using TBHP (70%in water) as an environmentally benign oxidant. This method affords a facile metal-free approach for synthesis of imidazole and purine nucleoside derivatives. The possible mechanistic pathway is also proposed on the basis of control experiments4. Metal-free,n-Bu4NI-catalyzed regioselective difunctionalization of unactivated alkenesA new synthetic approach toward difunctionalization of alkenes has been developed under metal-free conditions. Various carboxylic acids and amines could react smoothly with alkenes to give dioxygenation and oxyamidation products, respectively. This organocatalytic process delivers2-hydroxy alcohols directly from simple alkenes with high levels of region control.5. Metal-free, one-pot highly selective synthesis of (E)-vinyl sulfones and sulfoxides via addition-oxidation of thiols with alkynesWe have developed a highly selective one-pot method for the synthesis of (E)-vinyl sulfones and sulfoxides from thiols with terminal alkynes. The sulfones and sulfoxides could be obtained with excellent selectivity in good isolated yields. This new protocol is well warranted in synthetic organic, using simple materials and easy experimental procedure.