Lithium, organo-, reagents reactions with

Organocadmium compounds can be prepared from Grignard reagents or organo-lithium compounds by reaction with Cd(II) salts.180 They can also be prepared directly from alkyl, benzyl, and aryl halides by reaction with highly reactive cadmium metal generated by reduction of Cd(II) salts.181... 

Organocadmium compounds can be prepared from Grignard reagents or organo-lithium compounds by reaction with Cd(II) salts.136 Organocadmium compounds can also... 

All that has been said in this section applies with equal force to the use of organo-lithium reagents in the synthesis of alcohols. Grignard reagents are one source of nucleophilic carbon organolithium reagents are another. Both have substantial carbanionic char acter in their- car bon-metal bonds and undergo the same kind of reaction with aldehydes and ketones. 

For the synthesis of secondary amines, Beak, Basha and Kokko used iV-alkyl-0-methylhydroxylamines li and Ij. The method of treating 1 equivalent of amination reagent with 1 equivalent of methyllithium, followed by reaction with 1 equivalent of organo-lithium to be aminated, was found more effective than reacting 1 equivalent of amination reagent with 2 equivalents of the organoUthium (Scheme 8). ... 

Alvernhe and Laurent first developed a procedure for conversion of Grignard reagents to primary amines using acetone oxime 6c and butanone oxime 6d (Scheme 55) 22 23 However, the yields were low. They expanded their study to investigate how well organo-lithiums perform in their reaction with 6c or 6d 23. Phenyllithium gave a 1 4 mixture of aniline and the addition product of phenyllithium to the imine (Scheme 53, path e product) in the reaction with 6c while aziridine was obtained in the reaction with 6d (Scheme 56). 

Also other reaction types have been dealt with in CHEC(1984) and CHEC-II(19%) like reduction to alcohols (e.g., sodium borohydride), Wolff Kishner reduction, nucleophilic addition via reaction with Grignard reagents or organo-lithium compounds, and formation of imine type functional groups (e.g., hydrazones). New examples are the reaction of... 

Appreciable diastereoselectivity (50%) was found in the cycloaddition with buta-1,3-diene at -78 °C and the protiodesilylation of the diastereomeric mixture of the adducts with TBAF gave dihydrothiopyran with 51% ee (Scheme 28). Similar diastereoselectivity was observed in the reaction with organo-lithium and Grignard reagents which gave a-silyl sulfides in moderate yields with medium to good levels of asymmetric induction (de = 40-76%).45 As an example, the derivative with E = D gave with protiodesilylation a-deuterio benzyl methyl sulfide with 45% ee. These results lead to the conclusion that in both cases protiodesilylation occurs stereospecifically without loss of the induced chirality (Scheme 28). 

Aminomethylotion. The reagent reacts with Grignard reagents to form N,N-bis(trimethylsilyl)amines in 60-90% yield (equation I). A similar reaction with organo-lithium compounds requires added magnesium biomide for satisfactory yields. ... 

Acylation of organozinc reagents. Reaction of acyl chlorides with organozinc compounds catalyzed by palladium-phosphine complexes provides a general synthesis of ketones. The organozincs are readily available by treatment of the corresponding organo-lithium with ZnCh. Alkenylzinc compounds and a,p-unsaturated acyl chlorides react with retention of the stereochemistry. Isolated yields of ketones are 55-90%. 

Reaction with l-chloro-2-methylcyclohexene (1). This vinyl halide reacts with phenyllithium (5 equiv.) to give the bicyclo[4.1.0]heptane (2) in 90% yield. The paper presents evidence for the intermediacy of the cyclopropene a. Other organo-lithium reagents react in the same way, but yields are lower, 47% in the case of CHjLi. 

Arylboranes, which have a boron atom bonded to a benzene ring, are prepared from organo-lithium reagents by reaction with trimethyl borate [8(0013)3]. 

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