LDA equation

Our best understanding to date of this qV relation is that it has the same origin in the DFT-LDA equations as the Harris energy approximation. " The concept that certain fragments retain their identity in total energy calculations that was demonstrated by Harris... 

I-Alkynes from methyl ketones This reaction can be effected by conversion to Ihe enol phosphate followed by -elimination with LDA (equation I). In the case of a simple ketone such as 2-octanone the yield is low because of formation also of an allene. In such cases lithium tetramethylpiperidide is recommended as base. 

An asymmetric preparation of alkenylcyclopropanes has also been realized by the use of palladium(O) complexes carrying chiral ferrocenylphosphine ligands (equation 22)38. The requisite rt-allyl palladium intermediates can also be generated from allene and meth-ylenecyclopropane derivatives, 1839 and 1940, in the presence of palladium(O) complex and alkenyl or aryl halide (equations 23 and 24). The cobalt complexes, 20, similarly afford the corresponding alkenylcyclopropanes upon exposure to LDA (equation 25)41. 

Insertion of a bromocarbene unit into the Si—C bond has been observed in the reaction of 61 with CH2Br2 in the presence of LDA (equation 107)105 106. 

A great number of contributions devoted to synthesis and modification of Jt-exTTFs utilized anthraquinone and its derivatives as substrates. Thus, the synthesis of the first bridged cyclophanes 906 and 907 based on 1,3-dithiole units was carried out by a twofold olefination reaction of anthraquinone using reagents 904 or 905, which were deproto-nated with LDA (Equation 101) <1999CC1835>. 

Recently, Zunger and coworkers [18, 58-63] employed the semi-empirical pseudopotential method to calculate the electronic structure of Si, CdSe [60] and InP [59] quantum dots. Unlike EMA approaches, this method, based on screened pseudopotentials, allows the treatment of the atomistic character of the nanostructure as well as the surface effects, while permitting multiband and intervalley coupling. The atomic pseudopotentials are extracted from first principles LDA calculations on bulk solids. The single particle LDA equation,... 

Commonly, the metal M is lithium, when the reagents have been described as stannylanionoids. These reagents can readily be prepared from the tin halides and metallic lithium (equation 4-27), or the distannanes and an alkyllithium (equation 4-28), or the tin hydrides and LDA (equation 4-29) (see Section 19.1.1). 

Other acyclic ketones also afford only (Z)-enol silyl ethers. The regioselectivity appears to differ from that observed with LDA (equation I). 

The iV,iV-diethylamide of l-phenylsulfonylindole-3-carboxylic acid is lithiated at C2 and gives fair to good yields of addition products with typical carbonyl compounds (Equation (107)) <93JCS(P1)1425>. The acid can also be lithiated at C2 using LDA (Equation (108)). 

This type of reaction occurs at lower temperatures with the dianions formed from allylic acetoacetates, which can be prepared from the reaction of acetoacetates with two equivalents of lithium diisopropylamide (LDA, equations 11.13 and 11.14). 

Ojima and colleagues found that enamine (imine) 9 from aldehyde 8 readily cycUzed to indoles 10 upon treatment with LDA (equation 5) [5, 6]. The A-allyl group in 10 was removed by rhodium trichloride isomerization followed by acidic hydrolysis of the A-enamine (97% yield). Along similar lines. Filler s team reported an improved synthesis of 4,5,6,7-tetrafluoroindole 13 (equation 6) [7] over the method they had reported earlier. The improvements are in the reduction of nitrile 11 to phenethylamine 12 and the final oxidation to 4,5,6,7-tetrafluoromdole (13). 

For closed shell atoms, all the above equations become one-dimension-al and therefore are no more difficult to solve than the original LDA equations, (1),... 

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