Matthew D. Healy

Sterically crowded aryloxide compounds of aluminum

Abstract The chemistry of aluminum compounds containing sterically demanding aryloxide ligands is presented. In particular, those of compounds derived from 2,6-di-tert-butyl-4-methylphenol (BHT-H, from the trivial name butylated hydroxytoluene). The synthesis and structure of three-coordinate monomeric derivatives, and their ligand exchange reactions, are discussed in comparison to the more typical four-coordinate oligomeric aluminum alkoxide and aryloxide compounds. The reactions of the sterically crowded aryloxide compounds is divided into four general classes: oxidation and hydrolysis, the formation of Lewis acid-base complexes, the reaction with organic carbonyls, and the reaction with main group halides. Alane-aryloxide compounds are discussed separately, as are the 1,3-diphenyltriazenide derivatives. Finally, a discussion of the AlO bonding interactions in four-coordinate aluminum aryloxides is presented, giving spectroscopic and theoretical evidence for and against various postulates to explain the presence of short Al-O distances and large AlOC angles.

The reaction of indium(III) chloride with tris(trimethylsilyl)phosphine: a novel route to indium phosphide

InP has been prepared by the reaction of InCl3 with P(SiMe3)3; the intermediates and product have been characterised by X-ray photoelectron spectroscopy, elemental analysis, and X-ray powder diffraction.

Sterically crowded aryloxide compounds of silicon

Abstract The interaction of one equivalent of NaBHT (BHT-H = butylated hydroxytoluene) with Me 3 SiCl, Me 2 SiCl 2 and SiCl 4 gives Me 3 Si(BHT) ( 1 ), Me 2 SiCl(BHT) ( 2 ) and Cl 3 Si(BHT) ( 3 ), respectively, which have been characterized by 1 H NMR, IR spectroscopy and elemental analysis. The molecular structures of 1 and 2 have been determined by X-ray crystallography. Compound 1 , space group P 2 1 a , a 9.129(1), b 15.290(7), c 13.196(8) A, β 95.15(6)°, Z = 4. Compound 2 , space group P 2 1 a , a 9.069(3), b 15.189(4), c 13.117(8) A, β 94.86(4)°, Z = 4. The presence of π-interaction between the oxygen lone pair and the aryl ring is proposed to account for the large SiOC angles observed; 1 139.4(3)°, 2 140.0(2)°.

Sterically Crowded Aryloxide Compounds of Aluminum: Complexes with Diethyl Ether and Tetrahydrofuran

Abstract The Et2O and THF Lewis acid-base adducts of AIR(BHT)2 and AIR2(BHT) [R = Me, Et; BHT-H = 2,6-di-tert-butyl-4-methyIphenol], have been prepared and characterized by elemental analyses, 1H and 13C NMR spectroscopy.

Sterically crowded aryloxide compounds of aluminium: hydrides and homoleptic aryloxides

Interaction of [AlH3(NMe3)] and [AlH2Cl(NMe3)] with HOR1(R1= C6H2But2-2,6-Me-4) allows for the isolation of [AlH2(OR1)(NMe3)]1 and [AI(H)Cl(OR1)(NMe3)]2 respectively. Compound 1 exists in both mono- and di-meric forms in the solid state. The reaction of 1 with NH2But results in ligand redistribution to give [AIH(OR1)2(NH2But)]3. Similarly, multiple recrystallisation of 1 from Et2O allows for the isolation of [AIH(OR1)2(OEt2)]4, while addition of HOR2(R2= C6H3Ph2-2,6) to 1 yields the mixed aryloxide complex [AIH(OR1)(OR2)(NMe3)]5. Interaction of compound 1 with benzophenone results in the formation of the bridged dimer [{AIH(OR1)(µ-OCHPh2)}2]6. The reaction of 3 molar equivalents of HOR1 with LiAlH4 yields, in addition to [{Li(OR1)(OEt2)}2], compound 4, which reacts futher with H2O, HOR1 or NH2C6H2Cl3-2,4,6 to give [{AI(µ-OH)(OR1)2}2]7, [AI(OR1)3]8 or [AI(OR1)2(NHC6H2Cl3-2,4,6)]13 respectively. Compounds 8 and 13 form stable Lewis acid–base complexes [Al(OR1)3L][L = MeCN 9, pyridine (py)10, OPPh311 or OC(C5H9)But-4 12] and [Al(OR1)2(NHC6H2Cl3-2,4,6)L](L = Et2O 14, py 15 or 3,5-dimethylpyridine 16). The presence of a slow ligand exchange for compound 9 and 12 was investigated by 1H NMR spectroscopy. The molecular structures of 1, 3, 4, 8 and 12 have been confirmed by X-ray crystallography.