Ru,Rh And Co-catalyzed C(sp~2)-H Bond Functionalization

The transition-metal-catalyzed direct C-H bond functionalization is a very important route for the construction of C-C bond and C-heteroatom bonds.This method is often step-and atom-economy,and has become an effective way in organic synthesis.This dissertation focuses on(1)Ru-and Co-catalyzed C-H allylation of aromatics,and(2)Rh-catalyzed alkylation of olefins via C-H bond activation.Chapter 1 summarizes the research progress of transition-metal-catalyzed C-H allylation of aromatics and olefinic C-H bond functionalization.First,the progress of direct allylation of aromatics catalyzed by different transition metals including ruthenium,rhodium,cobalt,palladium,and nickel was presented.Subsequently,the research progress of transition-metal-catalyzed olefinic C-H bond functionalization covering the construction of C(sp2)-C(sp),C(sp2)-C(sp2),C(sp2)-C(sp3)bonds and C-heteroatom bonds was summarized.Chapter 2 is concerned with Pyridyl-directed[Cp*RhCl2]2-catalyzed alkenyl C-H activation and oxidative coupling with allylic alcohols.This method can provide(3-alkenyl aldehydes or ketones from simple substrates via C-H activation strategy.Pyridyl-directed cyclic olefins and acyclic olefins reacted with allyl alcohol smoothly.The 1-aryl and 1-alkyl substituted allyl alcohols can also react with different olefins.This method showed excellent regioselectivity,the reaction occurring at the y-position of allyl alcohol and the cis? position of pyridyl-directed olefins.Chapter 3 deals with the allylation of aromatics with allylamine catalyzed by{Ru(p-cymene)Cl2]2.For 2-phenylpyridine and 2-(para-substituted phenyl)pyridines,the reaction occurred at the ortho positions of the phenyl groups and afforded bisallylation products.For the 2-(meta-substituted phenyl)pyridines,either biallyllylated products or monoallylated products were obtained depending on steric hindrance of the substituents.This method is compatible with various functional groups such as NO2,COOH,CF3,OH,and OMe.A range of allylamines such as aromatic allylamines,aliphatic allylamines and hydroxylamines can be employed as the allylation reagents.In addition,the catalyst system is also applicable to the C-H allylation of pyrazolyl-or pyrimidyl-directed aromatics.Chapter 4 describes pyridyl-directed[Cp*Co(CO)l2]-catalyzed allylation of aromatics with allylamines.The reaction exhibited a high selectivity.When the two ortho-positions of the phenyl group are available,monoallylated products can be selectively obtained.This method suits for a wide scope of substrates and is compatible with various electron-withdrawing and electron-donating substituents on the aromatic rings.In addition,a pyrimidyl-directed allylation of indole was also performed,giving C2-allylated indole under the standard conditions.Chapter 5 presents pyridyl-directed[Ru(p-cymene)Cl2]2-catalyzed allylation of aromatics with allyl alcohols.The reaction was carried out under mild conditions.2-Phenylpyridine and para-substituted 2-arylpyridines gave diallylation products.The 2-(meta-substituted phenyl)pyridines yielded either monoallylated products or biallylated products depending on the substituents.Functional groups including COOH,CF3,OH,OMe,and COOEt groups can be tolerated.A variety of substituted allyl alcohols can be employed as the allylation reagents.The catalyst system also suited for the pyrazolyl-or pyrimidyl-directed allylation of aromatics.Chapter 6 is devoted to pyridyl-directed[Cp*Co(CO)l2]-catalyzed allylation of aromatics with allyl alcohol.The reaction occurred at the ortho position of the aromatics.When the two ortho-positions are available,monoallylated products can be formed selectively.The reaction suited for a wide scope of substrates and gave moderate to excellent product yields.When a substituted allyl alcohol is used,the reaction occurred at the y position of the allyl alcohol.This method is also applicable to pyrazolyl-and pyrimidyl-directed allylation of indoles.