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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]

1-(1,3-Benzothiazol-2-ylsulfanyl)propan-2-ol (C 10 H 10 NS 2 OH, LH) was used as a multifunctional ligand in reactions with aluminum trialkyls R 3 Al (R = i Bu, Et, t Bu). The reactions at 1:1 M ratio of reagents proceeded with formation of dimeric (R 2 AlL) 2 (R = i Bu, Et) complexes with a central Al 2 O 2 ring, whereas in a presence of an excess of R 3 Al the compounds [(R 2 Al)(R 3 Al)L] 2 (R = i Bu, Et) with the central Al 2 O 2 ring and R 3 Al molecules coordinated to nitrogen atoms were obtained. i Bu 3 Al reacted with the LH yielding monomeric complex t Bu 2 AlL independently on the molar ratio of reagents. In the compound, Al coordinates to the nitrogen atom to form intramolecular sp 2 -N donor bonding. The compounds [( i Bu 2 Al)( i Bu 3 Al)L] 2 ( 1 ), (Et 2 AlL) 2 ( 2 ) and t Bu 2 AlL ( 3 ) were synthesized as pure compounds and characterized. Among four heteroatoms of the ligand, only the oxygen and nitrogen atoms can form bonds with aluminum atoms, whereas two sulfur atoms are non-coordinative. The compounds 1 and 2 are active as an initiator of the ε-caprolactone polymerization. [ABSTRACT FROM AUTHOR]

We studied reactions of t Bu 3 M (M = Al, Ga) with 2-mercaptobenzoxazole. In the presence of strong Lewis bases, alkylaluminum o -isotiocyanatophenolates [ t Bu 2 Al(OC 6 H 4 NCS)(THF)] ( 1 ), [ t Bu 2 Al(OC 6 H 4 NCS)(3-picoline)] ( 2 ) were obtained as a result of heterocycle cleavage in the 2-mercaptobenzoxazolate ligand and Al–O phenolate bond formation. The reaction of t Bu 3 Al with 2-mercaptobenzoxazole in OEt 2 as a weak Lewis base produced the stable tetranuclear complex [ t Bu 2 Al(C 7 H 4 NOS)] 4 ( 3 ). The gallium compound [ t Bu 2 Ga(C 7 H 4 NOS)] 4 ( 4 ), isostructural to compound 3 , was formed as a stable complex irrespective of the kind of Lewis base. The molecular structures of 1 , 3 , and 4 were determined by single-crystal X-ray diffraction technique. [ABSTRACT FROM AUTHOR]