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Cyanocarbonylation

In the presence of KCN, cyanocarbonylation of iodobenzene takes place to form benzoyl cyanide (587)[428]. [Pg.209]

P-Dicarbonyl and P-cyanocarbonyl anions, which have been shown to react in an Sr 1 fashion at sp carbon centres, were also found to be active toward aromatic and heteroaromatic carbons under photochemical (Beugelmans et al, 1982) or electrochemical stimulation (Oturan et al, 1989). [Pg.72]

Cyanocarbonylation,2 Aromatic iodides are converted into aroyl nitriles by carbonylation catalyzed by 1 and in the presence of KCN. Isolated yields are about 50 85%. [Pg.477]

Two different carbon functional groups can be introduced simultaneously into 1,2-positions of aromatic skeletons based on a novel insertion reaction of arynes (101) into a carbonyl-cyanomethyl a-bond of a-cyanocarbonyl compounds (102) to produce 1,2-disubstituted aromatics (103).134... [Pg.312]

F. Mixed Cyanocarbonyl Metalates Prepared from Metal Carbonyl Derivatives and NaN(SiMes)2. 38... [Pg.1]

The cyanocarbonylchromates(O) [Cr(CO)5CN]- and cis-[CifCOMCN) ] -, which are formed by the oxidation of [Cr l,(CO)s]2-with aqueous solutions of KCN or with (CN)2 or ICN have been discussed earlier (55, 56). Further studies have shown that the reaction of metal carbonyls or their derivatives with solutions of KCN in liquid NH3 is a most advantageous method for the synthesis of new cyanocarbonyl metalates of transition metals, since, in liquid NH3, alkali cyanides are not subject to solvolysis, and also since the broad temperature range of -78 to +120°C may be employed. Thus, we have been able to obtain quantitative yields of the tricyano-tricarbonyl metalates (0)/ac-[M(CO)3(CN)3]3 (M = Cr, Mo, W) by direct reaction of the hexacarbonyls (21) ... [Pg.36]

It is, however, impossible to use this route to obtain cyanocarbonyl metalates having more than three CN ligands. The /e/racyanodicarbonyl metalates(O) of chromium, molybdenum, and tungsten (126) are readily accessible from the dicarbonyl complexes M(CO)2bipy2 (M = Cr, Mo, W), Cr(CO)2[(Ph2P)2CH J2, or Cr(CO)1I(Ph,P) C2H4]2 (125) with KCN in liquid NH3 at 120°C. [Pg.36]

In the course of our studies on the preparation of cyanocarbonyl metalates, especially those of Groups VIB and VIIB, encouraged by our successful synthesis of the "mixed cyanocarbonyl complexes Re(CO)3(NH3)2CN and [Re(CO)3NH3(CN)2], we extended our work to include the preparation of further complexes containing ligands other than CO and CN. ... [Pg.38]

Formation of Ni(CO)4 or Co(CO)4- by the cyanide method depends upon the stepwise substitution of the anion of the cyano complex by the iso-electronic carbon monoxide molecule. By treating Co2(CO)8 with potassium cyanide we obtained cyanocarbonyls of cobalt of low oxidation number (83). In reactions of the nitrosyl carbonyls of iron and cobalt, Behrens (86) substituted all the CO groups with CN to give K3[Co(NO)(CN)3] or... [Pg.18]

K2[Fe(NO)2(CN)2]. My former co-worker R. Nast (83) showed that the reaction of carbon monoxide with K4[Ni2I(CN)6] and K4[Ni°(CN)4] in liquid ammonia gave nickel cyanocarbonyl complexes with monovalent and zero-valent metal atoms. The isoelectronic hexacyanoiron(III) or tetra-cyanonickel(II) complexes correspond to the cyanocarbonyls [Feu(CN)5 CO]3-, [Ni (CN)3CO]2-, or [Ni°(CN)2(CO)2]2-. Cobalt is analogous to nickel in forming the complex [Co(CN)3CO]2-. According to our earlier work, [Fe"(CN)5CO]3- and [Fem(CN)6]3- are isosteric (87). Other structural investigations were concerned with tetracyano and tetracarbonyl complexes (88). [Pg.19]

The reactions of monoanions of /Fdicarbonyl and / -cyanocarbonyl compounds with aryl halides have been induced electrochemically187. Thus 4-bromobenzophenone and p-chlorobenzonitrile give, with 138 in DMSO, good yields of substitution products. [Pg.1434]

Decomposition of the relatively stable 2,3-diazido-i -phenyl-maleimide (33) in refluxing benzene led to high yields of N N-bis(cyanocarbonyl)aniline (85) . This result is in keeping with the... [Pg.570]

Jones, D.W., MotevalU, M., Shaw, G., and Shaw, J.D., The cyanocarbonyl group. Synthesis and crystal structure of an imidazole carbonyl cyanide, Ci2N5OH,7, J. Chem. Crystallogr., 28, 561, 1998. [Pg.308]

The oxaziridine 13a reacts with a variety of P-dicarbonyl and a-cyanocarbonyl compounds under base catalysis (Eq. 162).149... [Pg.59]

Enolates of (3-dicarbonyl and a-cyanocarbonyl compounds have a strong tendency to form diazo compounds with arenesulfonyl azides. a-Substituted substrates react normally to give azides482 483 but even then a diazo transfer (Eq. 166)484 or other transformations319 321 484 may occur as side reactions. [Pg.61]

Thermolysis of the acid chloride (178) at 800 °C gives cyanocarbonyl chloride (179) which reacts with acid to give the triazine (180) (Scheme 53) <83AG(E)785>. [Pg.618]


See other pages where Cyanocarbonylation is mentioned: [Pg.162]    [Pg.1]    [Pg.36]    [Pg.36]    [Pg.36]    [Pg.37]    [Pg.8]    [Pg.2896]    [Pg.318]    [Pg.3202]    [Pg.3428]    [Pg.59]    [Pg.60]    [Pg.129]    [Pg.129]    [Pg.130]    [Pg.131]    [Pg.106]   
See also in sourсe #XX -- [ Pg.269 ]




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A-cyanocarbonyl compounds

Cyanocarbonylation aryl iodides

Cyanocarbonyls

Cyanocarbonyls

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