Main-group organometallics

Another important reaction via transmetallation is carbon-metal bond formation by reaction with bimetallic reagents. This is a useful synthetic method for various main group organometallic reagents. 

Main group organometallics in synthesis and transformations of heterocycles 98JCS(P1)1343. 

A68. B. G. Ramsey, Electronic Transitions in Organometalloids, 1969. Confined to electronic spectra of Main Group Organometallics. 

Main group organometallic polymerization catalysts, particularly of groups 1 and 2, generally operate via anionic mechanisms, but the similarities with truly coordinative initiators justify their inclusion here. Both anionic and coordinative polymerization mechanisms are believed to involve enolate active sites, (Scheme 6), with the propagation step akin to a 1,4-Michael addition reaction. 

Wills, M. Main group organometallics in synthesis. Contemp. Org. Synth. 1996, 3, 201-228. 

The mass spectra of main group organometallic compounds have been discussed in many of the reviews listed in the Introduction, and here we only summarize some recent examples. 

Reactions of Main Group Organometallic Reagents with Cyclophosphazenes. 67... 

Jain VK (2005) Synthesis and purification of some main group organometallic precim-sors for compound semiconductors. Bulletin of Materials Science 28(4) 313-316... 

Structures of Main Group Organometallic Compounds Containing Electron-Deficient... 

In this review, emphasis will be placed first on definitive proof of structure for compounds of main group organometallic compounds that contain the electron-deficient or multicentered bonds described. Evidence for the occurrence of these systems in both liquid an gaseous states also will be given. Finally, this structural information will be used to elucidate the bonding in the molecules. 

Main-group organometallic compounds are versatile tools in organic synthesis, but their structures are complicated by the involvement of the multicenter, two-electron bonds and ion-dipole interactions that are involved in aggregate formation (5). Electron deficiency or Lewis acidity of the metallic center and nucleophilicity or basicity of the substituents are important considerations in synthesis. The complexity of the structures and interactions is, however, the origin of much of the unique behavior of these organometallic compounds. 

Most main group organometallic compounds undergo nucleophilic reactions with carbonyl groups, whereas 1,4-conjugate addition to enones... 

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