Recent Advances in the Preparation of Air Stable Organozinc Pivalates and their Applications in Organic Synthesis

This review discusses various methods for the preparation of air and water-stable organozinc pivalates containing aryl, heteroaryl, alkyl, alkenyl, benzyl and alkynyl scaffolds achieved via i) selective metalation (DoM) in the presence of a directing group (DG) in the aromatic core, ii) direct oxidative Zn metal insertion/or X/M exchange reaction followed by transmetalation with Zn(Opiv)2, which are then further functionalized by Negishi cross-coupling reactions, or trapping with different aryl, heteroaryl, alkenyl, alkynyl electrophiles used by transition metal catalysts (Pd, Co, Ni, Cu). Selective deprotonation of aryl or heteroaryl derivatives can be performed using LDA, TMP-Mg and TMP-Zn reagents in the presence of a directing group on the aromatic system. Different organozinc reagents based on aromatic and non-aromatic structures with electron-rich and electron-deficient substituents undergo transition metal-catalyzed C(sp2)-C(sp2), C(sp2)-C(sp) and C(sp2)-C(sp3) types of cross-coupling reactions with aryl and heteroaryl halides and diaryl disulfides under mild conditions with the sustainable catalytic process. The literature report shows that the polyfunctionalized nitrogen, oxygen and sulfur-based bioactive pharmaceutical scaffolds, natural products and target organic molecules are accessible using highly air and moisture-stable organozinc pivalates under sustainable coupling reaction conditions. Importantly, the sensitive functional groups are tolerable, and the commercially available substrates and inexpensive low toxic reagents can be employed with organozinc pivalates. In this context, this review article provides a detailed summary of the numerous synthetic strategies and practical methods for the preparation of aryl, alkenyl, benzyl and alkynyl organozinc reagents that can be isolated in the pure solid form. Additionally, some recently published examples demonstrating their catalytic application in organic synthesis are discussed. This review article demonstrates the various recently discovered novel methods for the preparation of air-and moisture-stable organozinc pivalates as a solid remarkedly covering a wide range of aryl, heteroaryl, alkyl, alkenyl, alkynyl and benzyl scaffolds have been reported. The -OPiv salt-stabilized organozinc pivalates achieved via selective metalation (DoM), oxidative Zn insertion, and X/metal exchange reaction followed by successful trans-metalation approaches with Zn(OPiv)2, Thus, reactive organozinc reagents smoothly react with various electrophiles in the presence of transition metal catalysts (Pd, Co, Cu and Ni) under mild and sustainable conditions produced C-C, C-N, C-S bond formation products. image