zinc pivalate

• CAS: 15827-10-8
• Catalog Number: ACM15827108
• Category: Main Products
• Molecular Weight: 267.63
• Molecular Formula: C10H18O4Zn
• Synonyms: zinc:2,2-dimethylpropanoate
• Appearance: White Powder

Case Study

Zinc Pivalate Used in the Synthesis of Organometallic Reagents of Magnesium-Zinc Pivalate Systems

Hernán-Gómez, Alberto, et al. Angewandte Chemie, 2014, 126(10), 2744-2748.

The magnesium-zinc pivalate systems RZnOPiv·Mg(OPiv)X·n LiCl (where OPiv = pivalate; R = aryl, heteroaryl or benzyl; X = Cl, Br or I) are stable because they are more resistant to humid air than traditional organometallic compounds.
Synthesis of magnesium-zinc pivalates
The synthesis of these pivalates involves the insertion of Mg into the organohalide RX, the magnesiumation of RX by salt activation (TMP)MgCl·LiCl or the MgI/MgBr exchange of RI or RBr with iPrMgCl·LiCl, all of which involve a common second step, namely, transmetallation reaction with zinc pivalate [Zn(OPiv)2].
The combination of RMgX (R = aryl, alkyl) and Zn(OPiv)2 in a THF solution results in fully transmetalated products, RZnX and Mg(OPiv)2, which appear to exist independently according to NMR and ESI mass spectrometry data. Tests conducted in the presence of air show that (aryl)ZnCl reagents are inherently more stable than (alkyl)ZnCl reagents. Notably, Mg(OPiv)2 enhances this stability by absorbing OH or O2 species and retaining H2O molecules, thereby reducing their availability to hydrolyze CZn bonds. In contrast, LiCl seems to decrease the stability of organozinc pivalate reagents, likely because it is integrated into the Zn structure, unlike Mg(OPiv)2, bringing H2O molecules closer to the ZnC bonds.

Preparation and Progress of Air-Stable Organic Zinc Pivalate

Dhayalan, Vasudevan, et al. European Journal of Organic Chemistry, 2024, 27(9), e202301263.

This study explored various methods for creating air and water-stable organozinc pivalates with aryl, heteroaryl, alkyl, alkenyl, benzyl, and alkynyl structures. These methods include:
· Selective metalation (DoM) utilizing a directing group (DG) in the aromatic core;
· Direct oxidative insertion of Zn metal or X/M exchange reactions, followed by transmetalation with zinc pivalate [Zn(Opiv)2]. Subsequent functionalization is achieved through Negishi cross-coupling reactions or by trapping with various aryl, heteroaryl, alkenyl, and alkynyl electrophiles facilitated by transition metal catalysts (Pd, Co, Ni, Cu).
Selective deprotonation of aryl or heteroaryl derivatives can be accomplished using LDA, TMP-Mg, and TMP-Zn reagents in the presence of a directing group on the aromatic structure. Various organozinc reagents, both aromatic and non-aromatic, featuring electron-rich and electron-deficient substituents, can participate in transition metal-catalyzed C(sp2)-C(sp2), C(sp2)-C(sp), and C(sp2)-C(sp3) cross-coupling reactions with aryl and heteroaryl halides and diaryl disulfides under mild and sustainable catalytic conditions.
Furthermore, highly air and moisture-stable organozinc pivalates enable access to polyfunctionalized nitrogen, oxygen, and sulfur-containing bioactive pharmaceutical compounds, natural products, and target organic molecules through sustainable coupling reaction conditions.