Alkylation Cu

Few comparisons have been made among the relative stabilities of other classes of organocopper compounds. Generally, for simple derivatives, the order of decreasing stability is RC=CCu > Aryl-Cu > Alkyl-Cu. For vinylcopper compounds, 2-butenylcopper is more stable than propenylcopper 294). The higher homologs of methylcopper and lithium dimethylcuprate are less stable (69, 276, 297). 

Another type of bidentate alkyl group is obtained by deprotonation of the phosphonium methylide (CH3)3P=CH2 and occurs in the dimeric alkyl [Cu(CH2)2P(CH3)2l2 (Figure 13). In this structure each copper atom has a cylindrical spd manifold with the linear sp hybrids forming two-center two-electron bonds with the alkyl carbons of two different (CH3)2P(CH2)2 groups. 

Moreover, in analogy with the alkyl—Cu chemistry, hydrido—Cu reagents might provide selective conjugate addition of hydride and compatibility with most functional groups. Two Cu complexes seem to be efficient for that purpose [27] ... 

In addition to CuCfi, some other compounds such as Cu(OAc)2, Cu(N03)2-FeCl.i, dichromate, HNO3, potassium peroxodisulfate, and Mn02 are used as oxidants of Pd(0). Also heteropoly acid salts comtaining P, Mo, V, Si, and Ge are used with PdS04 as the redox system[2]. Organic oxidants such as benzo-quinone (BQ), hydrogen peroxide and some organic peroxides are used for oxidation. Alkyl nitrites are unique oxidants which are used in some industrial... 

The carbonylation of aryl iodides in the presence of alkyl iodides and Zn Cu couple affords aryl alkyl ketones via the formation of alkylzinc species from alkyl iodides followed by transmetallation and reductive elimination[380]. The Pd-catalyzed carbonylation of the diaryliodonium salts 516 under mild conditions in the presence of Zn affords ketones 517 via phenylzinc. The a-diketone 518 is formed as a byproduct[381],... 

Alkyl- and aryl-pyridazines can be prepared by cross-coupling reactions between chloropyridazines and Grignard reagents in the presence of nickel-phosphine complexes as catalysts. Dichloro[l,2-bis(diphenylphosphino)propane]nickel is used for alkylation and dichloro[l,2-bis(diphenylphosphino)ethane]nickel for arylation (78CPB2550). 3-Alkynyl-pyridazines and their A-oxides are prepared from 3-chloropyridazines and their A-oxides and alkynes using a Pd(PPh3)Cl2-Cu complex and triethylamine (78H(9)1397). 

Organometallic chemistry (see p. 1199) is not particularly extensive even though gold alkyls were amongst the first organo-transition metal compounds to be prepared. Those of Au are the most stable in this group, while Cu and Ag (but not Au ) form complexes, of lower stability, with unsaturated hydrocarbons. 

M-C(t bonds can be formed by each of the metals. The simple alkyls and ai7ls of Ag are less stable than those of Cu while those of Au have not been isolated. Copper alkyls and ai7ls are prepared by the action of LiR or a Grignard reagent on a Cu halide ... 

The reaction of tertiary alkylthioenyne alcohols (205) with carbon dioxide [70-73 atm, 70-75°C, Cu(I) salts, triethylamine] leads to 4,4-dimethyl-5-(alkyl-thioethenylmethylene)-l,3-dioxolan-2-ones (206) (79KGS1617 79ZOR1319). 

Ni-Cr-Mo Ni-Mo Ni-Cu Chlorination processes Processes involving HCl and nonoxidising acidic chlorides Production and Distillation columns containing acidic chlorides HF alkylation Fluorination Applications where no pitting and no loss of reflectivity are necessary Valves, Bleaching operations Handling Pickling of... 

Metallocorroles (M = Cu, Ni or Pd) can also be alkylated under the same conditions as the metal-free corroles23,24 to give the N2i-alkylated products together with a small amount of C3 alkylated product ( f = Pd). Allyl halides or bulky alkyl halides react with nickel corroles also at the 3-position. 

A similar but asymmetric variant of the reaction, involving the radical addition of alkyl iodides and trialkylboranes to chiral azirine esters derived from 8-phenyl-menthol and camphorsultam, in the presence of a Cu(i) catalyst, has subsequently been reported [64]. The diastereoselectivity of the addition is variable (0-92% de)... 

The decomposition of diacyl peroxides (36) is catalyzed by various transition metal salts,46,167 for example, Cu+ (Scheme 3.28).168,169 A side reaction is oxidation of alkyl radicals by the oxidized fonn of the metal salt e.g. Cu2+). 

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