Rhenium complexes isocyanide

Rhenium isocyanide complex chemistry has not been nearly so extensively studied as that of other elements and so further efforts are obviously necessary. 

Carvalho et al. reported molecular orbital calculations on the electron-rich rhenium isocyanide complex ReCl(CNH)(H2PCH2CH2PH2) and the aminocarbyne complex [ReCl(CNH2)(H2PCH2CH2PH2)] (37). They found that in the isocyanide complex a negative charge is accumulated on the Cl and N atoms. These two sites may therefore compete for electrophiles however, the product of N attack is thermodynamically favored. 

In a three-component reaction, a cationic platinum isocyanide complex [(Ph3P)2Pt(CNR)Cl][BF4] is reacted with a /3-bromoamine and butyl lithium to give an imidazoldin-2-ylidene complex.This transformation can be a two-component reaction if the isocyanide ligand contains already the necessary amine functionality. This was shown for chromium, molybdenum, tungsten, and rhenium carbonyls. 

Since the organometallic chemistry of rhenium is surveyed in the companion series Comprehensive Organometallic Chemistry,6 every effort has been made to minimize overlap with these topics, although an occasional reference is made in the present review to certain alkyl, aryl, carbonyl and isocyanide complexes that may be covered more fully in the excellent review by Boag and Kaesz.6... 

Addition of electrophiles to electron-rich isocyanide complexes is a proven synthetic method for the synthesis of aminocarbyne complexes (5,6). Reaction of the trimethylsilyl isocyanide rhenium complex 34 with HBF4 was reported by Pombeiro and co-workers (68). It leads to loss of the trimethylsilyl group and formation of the parent aminocarbyne ligand CNHj [Eq. (28)]. The CNHj ligand is easily interconverted to the CNH... 

The rhenium(III) complexes with phosphine, isocyanide, and nitrogen ligands are molecular species, the metal atom being seven-coordinate. Solutions in nitrobenzene are non-conducting. The crystal structure of ReBr3(CN tol)4 and ReBr3(CO)2(bipy) are known. 

Rhenium(III) complexes, 143-164 cyanides, 143 alkyl isocyanides, 143 amides, 144 amidines, 146 amines, 144 arsines, 147 aryl isocyanides, 143 cyanates, 145 diazines, 144 diethyidicarbamato, 150 P-diketones, 149 dinitrogen, 144 N heterocycles, 144 nitriles, 146... 

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