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β-Hydroxy sulfones are important in organic synthesis. The simplest method of β-hydroxy sulfones synthesis is the hydrogenation of β-keto sulfones. Herein, we report the reducing properties of alkyl aluminum compounds R3Al (R = Et, i-Bu, n-Bu, t-Bu and n-Hex); i-Bu2AlH; Et2AlCl and EtAlCl2 in the hydrogenation of β-keto sulfones. The compounds i-Bu2AlH, i-Bu3Al and Et3Al are the at best reducing agents of β-keto sulfones to β-hydroxy sulfones. In reactions of β-keto sulfones with aluminum trialkyls, hydroalumination products with β-hydroxy sulfone ligands [R2AlOC(C6H5)CH2S(O)2(p-R1C6H4]n [where n = 1,2; 2aa: R = i-Bu, R1 = CH3; 2ab: R = i-Bu, R1 = Cl; 2ba: R = Et, R1 = CH3; 2bb: R = Et, R1 = Cl] and {[Et2AlOC(C6H5)CH2S(O)2(p-ClC6H4]∙Et3Al}n3bb were obtained. These complexes in the solid state have a dimeric structure, while in solutions, they appear as equilibrium monomer–dimer mixtures. The hydrolysis of both the isolated 2aa, 2ab, 2ba, 2bb and 3bb and the postreaction mixtures quantitatively leads to pure racemic β-hydroxy sulfones. Hydroalumination reaction of β-keto sulfones with alkyl aluminum compounds and subsequent hydrolysis of the complexes is a simple and very efficient method of β-hydroxy sulfones synthesis. [ABSTRACT FROM AUTHOR]

t‐Butyl derivatives play a significant role in the organometallic chemistry of group 13 metals. It was shown on the basis of reactions of t‐Bu3Al·OEt2 with [p‐RC6H4S(O)2C(H)2C(Ph) = O] (where R = CH3, Cl) β‐keto sulfones that the structure of the reaction products depends on the purity of the aluminum compound used. In the reactions, in addition to the expected complexes [p‐RC6H4S(O2)C(H) = C (Ph)‐OAl(t‐Bu)2] [where R = CH3 (2); R = Cl (4)] possessing β‐keto sulfone ligands, complexes with β‐hydroxy sulfone ligands [p‐RC6H4S(O2)C(H)2‐C (Ph)‐OAl(t‐Bu)2] [where R = CH3 (1); R = Cl (3)] were formed. Compounds 1 and 3 were the result of the hydroalumination reaction of the β‐keto sulfone ligands with t‐Bu2AlH, which is an impurity of t‐Bu3Al. These compounds are obtained, for the first time, as intermediate products in the hydrogenation reaction of β‐keto sulfones. In this work, during t‐Bu3Al·OEt2 production t‐Bu2AlH·OEt2 formed as a by‐product. Re‐examination of reaction conditions of AlCl3 with t‐BuMgCl resulted in a control of the t‐Bu2AlH·OEt2 by‐product content in t‐Bu3Al·OEt2. [ABSTRACT FROM AUTHOR]

The reaction of the N- tert -butyl amide of succinic acid with t Bu 3 M (M = Al, Ga) resulted in the formation of the new complexes [Al t Bu 2 {N(H)( t Bu)C(O)CH 2 CH 2 COO}] ( 1 ), [M t Bu 2 {N(H)( t Bu)C(O)CH 2 CH 2 COO}( t Bu 3 M)] [M = Al ( 2 ), M = Ga ( 3 ), and [Ga t Bu 2 {N(H)( t Bu)C(O)CH 2 CH 2 COO}] 2 ( 4 ). The aluminum complexes 1 and 2 contained seven-membered C 4 O 2 Al rings with the Al atom bonded to the oxygen atom and coordinated to the nitrogen atom. The reaction of t Bu 3 Ga with the N- tert -butyl amide of succinic acid resulted in the formation of a mixture of 3 and 4 . The gallium complex 3 was isostructural to 2 , whereas the gallium atoms in the dinuclear compound 4 were bonded to the carboxylate oxygens only forming a central Ga 2 C 2 O 4 ring. X-ray studies showed that the crystalline solid obtained after crystallization from the post-reaction mixture was composed of crystals of compound 3 and co-crystals of 3 and 4 . In all reactions, only the OH protons of the ligand reacted with t BuM groups with an alkane evolution, while NH protons remained unreactive. The reaction of t Bu 3 Ga with the N- tert -butyl amide of succinic acid in a 2:1 M ratio of the reagents in the presence of water proceeded with the formation of the unprecedented compound [(Ga t Bu 2 ) 2 (OH){N(H)( t Bu)C(O)CH 2 CH 2 COO}] ( 5 ) as the only product. Compound 5 was also obtained in the hydrolysis reaction of the mixture of compounds 3 and 4 isolated from the post-reaction mixture of t Bu 3 Ga with the N- tert -butyl amide of succinic acid. The molecular and molecular packing in the crystal structures of 1 – 3 and 5 were determined by single-crystal X-ray diffraction. Crystal structure examinations showed laminar structures of 1 , 3 , and 5 and a packed crystal network of 2 . [ABSTRACT FROM AUTHOR]