Cobalt-catalyzed C8-alkenylation Reaction Between Alkynyl Phosphonates And 1-Naphthylamine Derivatives

The oxidative olefination reaction of C-H bonds under the catalysis of transition metals has become an important method for constructing C-C bonds.This method has many advantages compared with traditional Heck reactions,such as simplicity of starting material,high atom economy,friendly to the environment,etc.The realization of alkenylation of aromatic hydrocarbon derivatives is mainly divided into two categories:one is the oxidative coupling of aromatic hydrocarbon derivatives with olefins to achieve the alkenylation of aromatic hydrocarbon derivatives;the other is the hydrogenation of aromatic hydrocarbon derivatives with alkynes to achieve the alkenylation of aromatic hydrocarbon derivatives.In this paper,the alkenylation of naphthylamine derivatives with asymmetric alkynes containing heteroatom P under the catalysis of transition metal cobalt is mainly studied.The main research contents are as follows:（1）We first introduce the research background of C-H activation,and summarize the two types of alkenylation of aromatic hydrocarbon derivatives under the catalysis of transition metals,and determine the research direction and content of this paper.（2）We mainly introduced the synthesis of substrates:（i）a series of N-（1-naphthyl）pyridylcarboxamides Compounds 1a-1i are obtained through condensation reaction using cheap and readily available pyridic acid and1-naphthylamine as raw materials.（ii）we used the simple structure,and easy to obtain acetylene as the starting material.After bromination,nucleophilic substitution reaction,alkynl phosphonates compounds 2a-2p were been synthesized.（3）We use N-（1-naphthyl）pyridylcarboxamide（1a）and acetylenic phospholipid compound（2a）as substrates to investigate the optimal reaction conditions.The optimal reaction conditions were obtained by optimizing the conditions such as base,solvent,catalyst,reaction temperature and reaction time.Then under the optimal reaction conditions,a series of alkenylation products of naphthylamine C8 were synthesized in one step,and such products have never been reported in previous literatures.（4）Based on the applicability of the positioning group,the investigation of free radical capture experiments,the investigation of intermolecular dynamics experiments,and based on the literature search and the structure of the target compound,we proposed a possible mechanism for the alkenylation reaction.All target compounds obtained in this paper were confirmed by ¹H NMR,¹³C NMR,³¹P NMR,¹⁹F,IR,EI and HRMS.