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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]

2-Mercapto-1,3-benzothiazole (mbztH) may act as a chelating or bridging ligand. In this study, reactions of mbztH with Me3Ga and Me3In were examined. The products were characterized by NMR spectroscopy, elemental analyses, melting point, and molecular weight determinations. Formation of mononuclear chelating complexes Me2M(mbzt) (M = Ga, In) was observed in solutions. Crystallization of Me2M(mbzt) yielded uncommon non-symmetrical dinuclear complexes Me4M2(mbzt)2, in which one metal is bonded to two sulfurs and the other to two nitrogens. [ABSTRACT FROM PUBLISHER]

Despite the fact that extensive research has been carried out, the oxygenation of alkyl magnesium species still remains a highly unexplored research area and significant uncertainties concerning the mechanism of these reactions and the composition of the resulting products persist. This case study compares the viability of the controlled oxygenation of alkylmagnesium complexes supported by β-diketiminates. The structural tracking of the reactivity of (N,N)MgR-type complexes towards O2 at low temperature showed that their oxygenation led exclusively to the formation of magnesium alkylperoxides (N,N)MgOOR. The results also highlight significant differences in the stability of the resulting alkylperoxides in solution and demonstrate that [(BDI)Mg(μ-η2:η1-OOBn)]2 (in which BDI=[(ArNCMe)2CH]− and Ar=C6H3 iPr2-2,6) can be easily transformed to the corresponding magnesium alkoxide [(BDI)MgOBn]2 at ambient temperature, whilst [(F3BDI)Mg(μ-OO tBu)]2 (in which F3BDI=[(ArNCMe)2CH]− and Ar=C6H2F3-2,4,6) is stable under similar conditions. The observed selective oxygenation of (N,N)MgR-type complexes to the corresponding (N,N)MgOOR alkylperoxides strongly contradicts the widely accepted radical-chain mechanism for the oxygenation of the main-group-metal alkyls. Furthermore, either the observed transformation of the alkylperoxide [(BDI)MgOOBn]2 to the alkoxide [(BDI)MgOBn]2 as well as the formation of an intractable mixture of products in the control reaction between the alkylperoxide [(F3BDI)MgOO tBu]2 and the parent alkylmagnesium [(F3BDI)Mg tBu] complex are not in line with the common wisdom that magnesium alkoxide complexes' formation results from the metathesis reaction between MgOOR and Mg−R species. In addition, a high catalytic activity of well-defined magnesium alkylperoxides, in combination with tert-butyl hydroperoxide (TBHP) as an oxygen source, in the epoxidation of trans-chalcone is presented. [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]

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]