【作者】 杨军；

【导师】 周向葛；

【作者基本信息】 四川大学 ， 有机化学， 2021， 博士

【摘要】 高价铑{本文特指[Cp*Rh(III)]}是一种活性较高的金属催化剂,在催化CR(R=H,C)键的活化方面十分有效,可以构建新的C-C键、C-O键、C-N键、C-X键,在环化等反应中也占据着重要的地位。近年来,铑参与的导向基团辅助的芳香化合物官能化反应取得了丰硕成果。但同时也存在一些不足,例如:铑催化的碳-杂原子(尤其是硫原子)偶联反应较少;反应类型多为两组分交叉偶联;铑金属在自然界中含量较少,催化剂的使用受到一定的限制;铑催化的氧化反应多数要与金属氧化剂联用等。另一方面,钴和铑位于同一族,具有相似的最外层电子排布和相似的化学反应活性。因此,钴作为铑的廉价替代品近年来得到了广泛使用。同时,钴和铑又位于不同周期,钴的半径小于铑,钴具有更低的电负性,使钴{本文特指[Cp*Co(III)]}和铑反应性有些许不同,可以依靠钴来进行一些铑难以实现的反应。本文针对铑和钴催化剂的这些特点,设计并进行了三种反应:针对铑催化的碳-杂原子(尤其是硫原子)偶联反应较少,发展了铑催化偶氮苯邻位碳氢活化硫醚化反应;针对铑催化的反应类型多为两组分偶联,同时钴可作为铑的廉价替代,发展了钴催化甲醛和芳基对萜烯的羟甲基芳基化的三组分反应;针对铑催化的氧化反应多数要与金属氧化剂联用等,进行了三氟乙酸代替铑与氧气结合,进行仿生催化氧化脱氨化反应的进行,再与羟胺进行重排反应,实现磺酰胺向酰胺化合物的转化。全文分为四章:1.第一章为绪论,总结文献中高价铑和高价钴催化的和本论文工作有关的部分反应。其中包括:芳香化合物的碳硫键的形成;芳香化合物与烯烃、醛基或亚胺的反应;芳香化合物的多组分反应;高价铑催化的氧化反应等。在此基础上,提出了本文的主要设想。2.第二章为铑催化偶氮苯邻位碳氢活化硫醚化反应偶氮苯是一类重要的有机化合物,可作为橡胶促进剂、有机染料和分子开关等,具有重要应用价值。本工作使用五甲基环戊二烯基氯化铑二聚体为催化剂,四氟硼酸银为氧化剂,偶氮苯为底物,选择性的实现了偶氮苯邻位碳氢活化单硫醚化的反应,得到了一系列偶氮苯硫醚化的衍生物,一系列包含氟、氯、溴、碘、甲氧基、酯基和硝基等官能团的底物均可兼容于反应,最高收率达99%。反应具有良好的区域选择性和官能团兼容性。3.第三章为钴催化的萜烯与甲醛和芳烃之间的羟甲基芳基化反应高烯丙醇及其衍生物用途广泛,可以作为合成子制备多种复杂化合物。本工作使用五甲基环戊二烯基钴为催化剂,六氟锑酸银为活化剂,乙酸为添加剂,实现了芳基和甲醛对萜烯的羟甲基芳基化反应,反应最高收率达99%。该反应使用廉价金属钴催化修饰多种长链萜烯,以30-81%的收率得到了一系列由C5-C45萜烯衍生而来的醇类化合物。反应的化学选择性取决于萜烯和甲醛的配位能力的强弱,反应的区域选择性取决于位阻和烯烃及导向基团的配位能力。反应具有好的原子经济性。4.第四章为促进磺酰胺向酰胺的转化酰胺化合物在天然产物和药物中广泛存在。本工作以磺酰胺作为底物,以三氟乙酸代替铑催化剂,与氧气结合,促进氧化脱氨化反应的进行,再与羟胺进行重排反应,实现磺酰胺向酰胺化合物的转化。反应经历了C-C键和C-N键的断裂。该反应的适用范围较广,可以实现二芳基甲胺,芳基烷基甲胺等胺类化合物的转化利用。通过高价铑金属催化碳硫偶联,实现了对苯胺化合物的邻位选择性硫醚化修饰。通过钴催化的三组分反应,部分解决了芳环和烯烃反应的区域选择性问题,以及芳香化合物对萜烯和醛类化合物加成的化学选择性问题。更多还原

【Abstract】 High valent rhodium {refer to [Cp*Rh(III)]} is a kind of metal catalyst with high activity.It is very effective in the activation of C-R(R = H,C)bonds.It can help forming new C-C bond,C-O bond,C-N bond,C-X bond and plays an important role in cyclization.In recent years,great achievements have been made in the functionalization of aromatic compounds with assistance of rhodium catalyst and coordination directing groups.However,there are also some shortcomings involving less examples of carbon-heteroatom(especially sulfur atom)coupling reactions;reaction types are mostly two-component coupling reactions;rhodium metal content is poor in nature and the usage is limited;oxidation reactions catalyzed by rhodium are mostly combined with metal oxidants etc.On the other hand,cobalt and rhodium are located in the same group and have similar outermost electron arrangement which results in the similar chemical reactivity.So cobalt is widely used as a cheap substitute for rhodium.At the same time,cobalt and rhodium are located in different periods,and the radius of cobalt is smaller than that of rhodium.Cobalt has lower electronegativity.These facts suggest the slight difference in the reactivity of cobalt {refer to[Cp*Co(III)]} and rhodium.Many reactions that is difficult to achieve by rhodium would be carried out by cobalt.According to these characteristics,three kinds of reactions have been designed and carried out.Rhodium-catalyzed ortho C-H activation and thioarylation of azobenzene is developed to overcome the scarcity of rhodium-catalyzed carbon-heteroatom(especially sulfur atom)coupling reactions;in view of the fact that rhodium-catalyzed reactions are mostly two-component coupling and cobalt is a cheap substitute for rhodium,three components reaction of cobalt-catalyzed hydroxymethylarylation of terpenes with formaldehyde and arenes has been developed;most of the oxidation reactions catalyzed by rhodium are combined with metal oxidants,it was found that trifluoroacetic acid can replace rhodium to combine with oxygen for biomimetic catalytic oxidation reaction,and then proceeds a rearrangement reaction with hydroxylamine to achieve the conversion from sulfonamides to amides without metal catalysis.The paper is divided into four chapters:1.The first chapter is introduction,which summarizes some reactions catalyzed by high valent rhodium and cobalt related to this paper.Including the formation of carbonsulfur bonds of aromatic compounds;the reactions of aromatic compounds with olefins,aldehydes or imines;the multicomponent reactions of aromatic compounds;and the rhodium(III)-catalyzed oxidation reactions.And the main ideas of this paper are briefly described based on these facts.2.The second chapter is rhodium(III)-catalyzed thiolation of azobenzenesAzobenzene is a kind of important organic compounds and has important applications as rubber accelerator,organic dye and molecular switch.In this reaction,pentamethylcyclopentadienyl rhodium chloride dimer was used as catalyst,silver tetrafluoroborate was used as oxidant,and azobenzene was used as substrate.The reaction of ortho C-H activation of azobenzene and mono thioarylation was realized.A series of sulfer-containing azobenzene derivatives were obtained.Functional groups such as fluorine,chlorine,bromine,iodine,methoxy,ester and nitro were compatible.The highest yield was obtained as 99%.The reaction has good regioselectivity and functional group tolerance.3.The third chapter is cobalt-catalyzed hydroxymethylarylation of terpenes with formaldehyde and arenesHomoallylic alcohols and their derivatives are widely used in the synthesis of various complex compunds.In this reaction,pentamethylcyclopentadienyl cobalt was used as the catalyst,silver hexafluoroantimonate was used as activator,acetic acid was used as the additive.Hydroxymethylarylation of terpenes with formaldehyde and arenes was achieved with the highest yield of 99%.A series of alcohols derived from C5-C45 terpenes were obtained by cheap cobalt as catalyst in 30-81% yield.The chemoselectivity of the reaction depends on the coordination ability between terpenes and formaldehyde.The steric hindrance and coordination abilities of isoprene and directing group dominate the regioselectivity.This protocol features high atomic economy.4.The forth chapter is conversion of sulfonamide to amideAmides exist widely in natural products and drugs.In this reaction,sulfonamide was used as the substrate,it was found that trifluoroacetic acid could replace rhodium catalyst,and combine with oxygen to carry out the oxidative deamination reaction,followed by rearrangement reaction with hydroxylamine.The conversion of sulfonamides to amides without metal catalysis was realized including the cleavage of C-C bonds and C-N bonds.The reaction has a wide range of applications and realizes the conversion and utilization of diarylmethylamine,arylalkylmethylamine and other amine compounds.Ortho-selective thioetherification of aniline was realized by carbon-ulfur coupling with high valent rhodium.The regioselectivity of aromatic rings and terpenes,and the chemical selectivity of aromatic compounds for the addition of terpenes and aldehydes were partly solved by cobalt-catalyzed three-component reactions.更多还原