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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 R 3 Al (R = Et, i -Bu, n -Bu, t -Bu and n -Hex); i -Bu 2 AlH; Et 2 AlCl and EtAlCl 2 in the hydrogenation of β-keto sulfones. The compounds i -Bu 2 AlH, i -Bu 3 Al and Et 3 Al 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 [R 2 AlOC(C 6 H 5 )CH 2 S(O) 2 ( p -R 1 C 6 H 4 ] n [where n = 1,2; 2aa : R = i -Bu, R 1 = CH 3 ; 2ab : R = i -Bu, R 1 = Cl; 2ba : R = Et, R 1 = CH 3 ; 2bb : R = Et, R 1 = Cl] and {[Et 2 AlOC(C 6 H 5 )CH 2 S(O) 2 ( p -ClC 6 H 4 ]∙Et 3 Al} n 3bb 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 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.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.

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]

Complexes containing aminophenolate ligands are considered as very efficient initiators of ring-opening polymerization (ROP). Our systematic studies of the reactions of two selected aminophenols, 2-[( p-tolylamino)methyl]-4-(2,4,4-trimethylpentan-2-yl)phenol (L'H2) and 2-cyclohexylaminomethyl-4-methylphenol (L″H2), with alkyl compounds of aluminium, gallium and zinc resulted in the formation of a variety of products depending on the type of metallic centre and alkyl groups bonded to metal atoms. New trinuclear aluminium complexes (Me5Al3(L′)2 ( 1) and Me5Al3(L″)2 ( 2)), monomeric aluminium ( tBu2Al(L'H) ( 3) and tBu2Al(L″H) ( 5)) and gallium ( tBu2Ga(L'H) ( 4) and tBu2Ga(L″H) ( 6)) compounds, and dinuclear gallium (Et2Ga(L″H)·Et3Ga ( 7)) and zinc ( tBuZn(L″H)]2 ( 8)) complexes were isolated and characterized. The molecular and crystal structures of 7 and 8 were determined on the basis of an X-ray diffraction study. Polymerization tests showed that only three complexes ( 6- 8) had activity in the ROP of ε-caprolactone, whereas 1- 5 were inactive in ROP. [ABSTRACT FROM AUTHOR]

Reactions of the chiral alcohol rac 6,7-dihydro-5H-pyrrolo[1,2- a ]imidazol-7-ol [(R,S)-LH] with R 3 Al (R = t Bu, Et) have been studied. An influence of reaction conditions on the product structures and distributions was found. The dimeric products (Al 2 R 4 L 2 ) [R = t Bu ( 1 ), R = Et ( 2 )] were formed in the reactions of R 3 Al with one equivalent of (R,S)-LH as mixtures of the heterochiral (R,S) and homochiral (R,R) and (S,S) diastereomers. The X-ray diffraction measurements of the (R,S)- 1 and (R,S)- 2 showed dinuclear complexes with bridging ON ligands and 10-membered C 4 N 2 O 2 Al 2 central cycles. The molecules contain two chiral ligands demonstrating (R) and (S) configurations of CO carbon atoms. Polymerization tests showed that the complexes 1 and 2 have activity in the ROP of ε-caprolactone. Kinetic studies revealed first order reaction of polymerization. [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]