Group 13 alkyl compounds incorporating aliphatic and aromatic diolate ligands

Use of group 13 aryloxides for the synthesis of green chemicals and oxide materials

In this work, group 13 metal aryloxides [Al(MesalO)3] (1), [Me2Ga(MesalO)]2 (2), [AlLi3(MesalO)6] (3) and [Me2GaLi(MesalO)2(THF)] (4), were obtained by reaction of methyl salicylate (MesalOH) with group-13 alkyls MMe3 (for M...

Reactions of Trimethylaluminium: Modelling the Chemical Degradation of Synthetic Lubricants

In investigating and seeking to mimic the reactivity of trimethylaluminium (TMA) with synthetic, ester-based lubricating oils, the reaction of methyl propionate 1 was explored with 1, 2 and 3 equivalents of the organoaluminium reagent. Spectroscopic analysis points to the formation of the adduct 1(TMA) accompanied only by the low level 1:1 production of Me2 AlOCEtMe2 2 and Me2 AlOMe 3 when an equimolar amount of TMA is applied. The deployment of excess TMA favours reaction to give 2 and 3 over 1(TMA) adduct formation and spectroscopy reveals that in hydrocarbon solution substitution product 2 traps unreacted TMA to yield 2(TMA). The 1 H NMR spectroscopic observation of two Al-Me signals not attributable to free TMA and in the ratio 1:4 suggests the formation of a previously only postulated, symmetrical metallacycle in Me4 Al2 (μ2 -Me)(μ2 -OCEtMe2 ). In the presence of 3, 2(TMA) undergoes thermally induced exchange to yield Me4 Al2 (μ2 -OMe)(μ2 -OCEtMe2 ) 4 and TMA. The reaction of methyl phenylacetate 5 with TMA allows isolation of the crystalline product Me2 AlOCBnMe2 (TMA) 6(TMA), which allows the first observation of the Me4 Al2 (μ2 -Me)(μ2 -OR) motif in the solid state. Distances of 2.133(3) Å (Al-Mebridging ) and 1.951 Å (mean Al-Meterminal ) are recorded. The abstraction of TMA from 6(TMA) by the introduction of Et2 O has yielded 6, which exists as a dimer.