Lewis base stabilization

Transition Metal Complexes of Lewis Base-Stabilized... 

Scheme 14. General synthetic pathways for the synthesis of monomeric, Lewis base-stabilized compounds dmap—M(R2)E(Tms2)...

The heterocycles can be cleaved by reaction with 4-(dimethylamino)pyri-dine, yielding Lewis base-stabilized monomeric compounds of the type dmap—M(R2)E(Tms)2 (M = Al, Ga E = P, As, Sb, Bi). This general reaction now offers the possibility to synthesize electronically rather than kinetically stabilized monomeric group 13/15 compounds. These can be used for further complexation reactions with transition metal complexes, leading to bimetallic complexes of the type dmap—M(Me2)E(Tms)2—M (CO) (M = Al, Ga E = P, As, Sb M = Ni, Gr, Ee). 

Complexes (1063) have been obtained by the reaction of Ni(CO)4 with monomeric Lewis base-stabilized aluminum pnictines [dmap-AlMe2-E(SiMe3)2] (E = P, As, Sb).2555... 

Reversible pyridine dissociation yields the non-Lewis base stabilized imido complex [Cp(NHAr) Ti=NAr] (54). This coordinatively unsaturated species undergoes a [2 + 2] cycloaddition reaction with allene to give an azatitanocyclobutane (55), which is then protonated to the /mamido complex. Elimination of enamine occurs followed by isomerization to the energetically more favorable imine. 

Lewis base-stabilized monomers dmap M(R2)E(SiMe3)2 are also interesting candidates for reactions with group 13-trialkyls, yielding group 13/15 compounds containing both M-E a- and M-E dative bonds within a single molecule (Scheme 16). 

Scheme 16. Reaction of Lewis base-stabilized monomers with group 13 trialkyls.

Lewis acids (R3M), 229-232 Lewis bases (ER 3M), 95, 229-232 Lewis base stabilized compounds, 259, 275-291 Ligands... 

Figure 12 Structures of Lewis base-stabilized trisazidogallanes.

Figure 37 Structures of two Lewis base-stabilized gallium subhalides 470 and 471.

Synthesis of Lewis Base-Stabilized Monomers of the Type Base—M(R2)ER 2... 

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