Heteroatomic coupling

Aromatic carbon-heteroatom coupling reactions with participation and formation of heterocycles 98JCS(P1)2615. 

V. Mechanisms for the Functionalization Sequence Carbon-Heteroatom Coupling to Release the Product... 

A. Five-Coordinate Intermediates Involved in Carbon-Heteroatom Coupling Reactions from Pt(TV)... 

Heteroatomic coupling sites such as halogen are not necessary in the polymerization process, and all atoms present in the monomer are also present in the polymer. 

Characterization of organometalhc agents through multmuclear analysis by correlating fluorine chemical shifts and fluonne-heteroatom coupling constants... 

Step growth reactions involving the homo- and heteropolycondensation of various bifunctional unsaturated monomers in the presence of transition metal-based coordination catalysts have appeared to be a very useful synthetic tool for the preparation of low and high molecular weight polymers with an unsaturation in the polymer backbone. These reactions lead to unsaturated hydrocarbon and non-hydrocarbon polymers where polymeric chains are formed by carbon-carbon and carbon-heteroatom coupling respectively. 

Transition metal-catalysed carbon-heteroatom coupling reactions primarily comprise the carbonylation polycondensation of dibromoarenes with aromatic diamines and bisphenols in the presence of carbon monoxide... 

Carbon-heteroatom coupling reactions including carbonylation and carboxy-lation polycondensations, promoted by transition metal catalysts, are becoming a promising route for various types of new condensation polymer. 

The general catalytic cycle for this carbonylation coupling reaction is analogous to direct carbon-heteroatom coupling [scheme (39)] except that carbon monoxide insertion takes place after the oxidative addition step and prior to the nucleophilic attack of the amine [scheme (40)] ... 

Only derivatives of the 1,2-oxathiole series have been obtained by direct heteroatom coupling. The successful bond formation involves some type of activation of the sulfur atom in 3-hydroxypropanethiol or its oxidized derivatives. TTie parent 1,2-oxathiolane system (106) was recently reported (81CC741) to be obtained from the vacuum pyrolysis of (105), as shown in Scheme 23. A cyclic oligomer is believed to be generated first and (106) is formed on standing. Oxidation of (106) yields the mono- and di-oxide which have been known for some time. The monoxide may be obtained by the oxidative coupling of 3-hydroxypropane thiol (equation 22). Chlorine is the most frequently used oxidant and... 

Only one derivative of the 2,1-benzoxathiole system has been reported in its lowest oxidation state (75JA6909), and involves direct heteroatom coupling as indicated in equation (44). Preparative routes to oxidized forms of 3H- 1,2-benzoxathiole (76CJC3012) and 5H- 2,1-benzoxathiole (66HC(21-1)76) are shown in equation (45) and Scheme 45, respectively. 

Heteroatom couplings produce aryl- or vinyl- N, -S, or -P bonds... 

P. F. Engel and M. Pfeffer, Carbon-Carbon and Carbon-Heteroatom Coupling Reactions of Metallacarbynes, Chem. Rev., 1995, 95, 2281. 

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