Organogalliums

The fractions were claimed to contain benzene, Ga.4>3, ethanol and water, more polar organogallium compounds (ethers and others) 7MHC1, atomic and ionic gallium. 

Prior to 1995 no such inorganic compound, save perhaps for borazine, could boast of aromaticity. The utilization of m-terphenyl sterically demanding ligands in organogallium chemistry would change this forever. 

Organogallium compounds, 12 361 Organogermanium compounds, 12 554 Organogold compounds, 12 707-708 Organohalogen compounds (AOX), 26 398 Organohalogens, in Grignard reactions, 12 824... 

The following supraicosahedral organogallium clusters have been characterized structurally (Figures 1-12 and 1-13 see also Chapters 2.3.4.2.5 and 2.3.4.2.6) ... 

Zhu, C. Yuan, F. Gu, W. Pan, Y. (2003) The first example of enantioselective isocyanosilylation of meso-epoxides with TMSCN catalyzed by novel chiral organogallium and indium complexes., Chem. Commun., 692-693. 

Some organogallium fluorides are known. These have cyclic structures (R2GaF) , where n — 3 or 4,622 and so differ from the chlorides and bromides (R2GaX)2 which are halogen-bridged dimers. 

Organogallium reagents, RsGa, have been added enantioselectively to aldehydes, using TiCl4 as a Lewis acid catalyst, with a chiral salan ligand.258... 

Reaction of Organogallium Compounds 9.14.4.2.1 Addition to carbonyl compounds... 

Organogallium compounds are good nucleophiles for performing addition reactions to carbonyl functionalities. Alkylation, allylation, aldol condensation, and the Reformatsky reaction proceed readily with organogallium reagents. 

By the catalysis of GaCl3 and 2,6-di(/-butyl)-4-methylpyridine, five- or six- membered-ring ct,a -disubstituted ketones are ethenylated at the cr-carbon with trimethylsilylethyne at 180 °G. The roles of the base are believed to inhibit decomposition of the products and to promote photodegallation of the organogallium intermediates (Scheme 140).429... 

Aromatic hydrocarbons are alkenylated with allenylsilane in the presence of GaCl3 at — 90 °C. A modest level of 0r// 0-seleetivity is observed. Organogallium electrophiles generated from allenes and GaCl3 are active intermediates in this reaction. While the allenylsilane reacts exclusively at the central carbon, 1,2-alkadiene reacts at the terminal carbon predominantly (Scheme 151).446... 

The hexanuclear organogallium oxide fluoride, Mes6Ga604F4 (Mes = mesitylene) has been prepared by the reaction of Mes2GaF with water in THF at ambient temperature [14]. The structure of Mes6Ga604F4, which crystallizes with a mole ofTHF, is a distorted octahedron of Ga atoms in which all eight faces are capped by O/F... 

---