Carboxylative coupling

Copper complex-catalysed carboxylation polycondensation of dibromoalkanes with arenediyls in the presence of carbon dioxide [scheme (17)], although producing low molecular weight polyesters in moderate yields, also represents pioneering efforts in the use of carbon dioxide as a non-petroleum-based carbon source [5], 

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Biotin acts as a carboxyl group carrier in a series of carboxylation reactions, a function originally suggested by the fact that aspartate partially replaces biotin in promoting the growth of the yeast Torula cremonis. Aspartate was known to arise by transamination from oxaloacetate, which in turn could be formed by carboxylation of pyruvate. Subsequent studies showed that biotin was needed for an enzymatic ATP-dependent reaction of pyruvate with bicarbonate ion to form oxaloacetate (Eq. 14-3). This is a (3 carboxylation coupled to the hydrolysis of ATP. 

Scheme 5.11 Carboxylative coupling of organostannanes with organic halides, showing a scrambling of the ligands during the carboxylation/esterification step [47],...

Decarboxylative Dimerization The Kolbe Reaction De-carboxylic-coupling... 

Palladium-catalyzed carboxylation of allyl stannanes and carboxylative coupling of allyl stannanes and allyl halides... 

As in the direct stannane carboxylation the carboxylative coupling is thus far limited to allyl stannanes RSnBu3 with R = PhCH2, Ph, vinyl, PhC=C- all fail to react. The structure of the... 

Kolbe Reaction Anodic Oxidation of Carboxylates Coupling of... 

Carboxylative coupling of allylstannanes and allyl halides under carbon dioxide (50 atm) affords unsaturated esters. ... 

Another attempt is to prepare films with electronically isolated oligothiophene molecules in uniaxially oriented matrices. The matrix can consist of cyclic siloxanes [ 108] or dextrines which both possess cavities of defined diameter and length. Oligothiophenes can diffuse into the anisotropic matrix. Substitution with certain polar head-groups allows for a strong bonding to the metal substrate, i.e. nitriles or carboxyles couple to Pt, thiols to Au. 

Nickel tetracarbonyl is used in the manufacture of nickel powder and nickel-coated metals, and as a catalyst in carboxylation, coupling, and cyclization reactions. It can form from the contact of carbon monoxide with nickel. 

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