Halide abstraction pseudohalides

Abstract The use of organoaluminum-based Lewis acids (A1R X3 R = alkyl, alkynyl, X = halide or pseudohalide) in the period 2000 to mid-2011 is overviewed with a focus on (1) stoichiometric reactions in which one of the organoaluminum substituents is transferred to the substrate (e.g., the opening of epoxides, 1,2-additions to carbonyl compounds, coupling with C-X, and Reissert chemistry) and (2) asymmetric, often catalytic, reactions promoted by Lewis acid catalysts derived from organoaluminum species (e.g., use of auxiliaries with alanes, Diels-Alder, and related cycloaddition reactions, additions to aldehydes and ketones, and skeletal rearrangement reactions). 

Abstract During the last decades a powerful set of protocols featuring C(sp )-N bond formation have emerged as convenient alternatives for the assembly of enamine and enamides. Those methods consist of mostly palladium-catalyzed oxidative amidations of alkenes and both palladium- and copper-catalyzed cross-couplings between generally vinyl halides or pseudohalides and amines or amides. In this review recent advances in both types of processes will be disclosed. Additionally, the synthetic value of the title processes will be illustrated by describing relevant total syntheses of natural products involving vinylation process as the key step. 

Mercury(II) salts have been employed as reagents for the abstraction of halides and pseudohalide ligands from complexes of transition metals,26 Eq. 3.4 ... 

Tertiary phosphines form a wide range of complexes of the type PtX2(PR3)2 (X - halide, pseudohalide R = alkyl, aryl or mixed alkylaryl). Space limitations preclude this chapter becoming a compendium of known compounds, therefore for each individual complex the reader is directed to Chemical Abstracts, Gmelin or the book by McAuliffe which contains extensive tabulations of compounds.1225 In this chapter we outline the general methods of synthesis, the properties, and the structures and spectral features which we expect to be found with this class of compounds. 

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