Organometal lithium

Clark, P.W. and Mulraney, B.J., Synthesis and physical properties of chlo-rodi(o-tolyl)phosphine, lithium di(o-tolyl)phosphide and the diphosphine series (o-tolyl)2P(CH2)nP(o-tolyl) (n = 1-4,6,8), /. Organomet. Chem., 217,51,1981. 

J. P. Leal, J. A. Martinho Simoes. Standard Molar Enthalpies of Formation of Lithium Alkoxides. J. Organometal. Chem. 1993, 460, 131-138. 

The use of lithium aluminum hydride gives slightly lower yields and probably involves a displacement reaction by hydride ion. The zinc-copper couple technique probably involves formation of an organozinc intermediate. Sodium, magnesium, and aluminum metal may be used to replace the zinc-copper couple [59a, b]. These organometal intermediates react with aldehydes and... 

Scheme 16). This regioisomer is also obtained in appreciable amounts if bulky lithium organometallies are used. Intramolecular carbolithiations have been reported, such as the cyclization of 5-alkynyl-lithium compounds to furnish the cyclized products in low yields.3... 

Artamkina, G. M. et al., J. Organomet. Chem., 1979, 182, 185 The THF-containing complexes formed between trinitrobenzene and the lithium or potassium salts of trimethyl-, triethyl- or triphenyl-germanate, -silanate or -stannate decompose explosively on heating, though trinitrobenzene—potassium trimethylstan-nate decomposes explosively at ambient temperature. 

Bailey, W. F. Brubaker, J. D. Jordan, K. P. Effect of solvent and temperature on the lithium-iodine exchange of primary alkyl iodides reaction of tBuLi with 1-iodooctane in heptane-ether mixtures./. Organomet. Chem. 

Normant, J.-F. Synthesis of selectively fluori-nated substrates via organometallic reagents derived from CF2=CFC1, CF2=CC12, CF2=CH2. J. Organomet. Chem. 1990, 400,19-34. Schmidt, R. R. Talbiersky, J. Russegger, P. Generation of functionally substituted vinyl-lithium compounds. Results and calculations. Tetrahedron Lett. 1979, 4273-4276. 

For a literature review dealing with the mechanism of the lithium-halogen interchange, see W. F. Bailey and J. J. Patricia, J. Organomet. Chem., 352, 1 (1988). 

Lithium derivatives of type 311 (route a in Fig. 119) can be obtained from Mannich bases that have suitably reactive moieties toward organometals, by reaction with... 

Organometals R-M are commonly prepared by metathesis of a transition metal complex with substitution-labile carbanio-noid reagents such as Grignard and lithium derivatives. 

There has been only a few reports on reactions of small rings with metal ynolates. Oxiranes are much less electrophilic than carbonyls and sometimes need activation by Lewis acids or Lewis-acidic organometals. The lithium-trimethylaluminum ate complex of i/ZyZ-substituted ynolate 105 reacts with the oxirane 106 to give the y-lactone 107 (equation 44), while lithium silyl-substituted ynolates are inert to oxiranes. There have been no reports using carbon-substituted metal ynolates. 

The reaction of the lithium salt of (trimethylsilyl)diazomethane with trimethylchlorosilane was reported to give bis(trimethylsilyl)diazomethane D. Seyferth, T. C. Flood, J. Organomet. Chem. 1971, 29, C25. 

Thiazolines activated with an equivalent of BF3 readily react with a wide range of organometals, giving rran -4,S-disubstituted thiazoles stereoselectively. Alkyllithiums, Grignard reagents, lithium alkynides, nitronates, ester and ketone enolates have been employed as the nucleophile. Stereocontrolled construction of three contiguous asymmetric centers is performed with a lithiated isothiocyanatoacetate, and the product is successfully transformed to (+)-biotin (Scheme 27). 

Villieras, J., Perriot, P., Bourgain, M., Normant, J. F. Enolates of esters. V. Preparation of the lithium analogs of Reformatsky reagents from a,a-dichloro and a-monohalo esters. Reactivity. J. Organomet. Chem. 1975,102, 129-140. 

Armstrong, D. R., Barr, D., Davidson, M. G., Hutton, G., O Brien, P., Snaith, R., Warren, S. Experimental and molecular orbital calculational study of the stereoselective Horner-Wittig reaction with phosphine oxides control of stereoselectivity by lithium. J. Organomet. Chem. 1997, 529, 29-33. 

Epoxysilanes, upon ring opening with organometals containing lithium and copper, give rise to adducts which either under the reaction conditions or upon treatment with KH can be stereo-specifically converted to the corresponding (E)- and (Z)-alkenes, respectively <89JOC2043>. 

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