56252-55-2

Usage

Uses

Used in Polymer Production Industry:
METHYLALUMINUM BIS(2,6-DI-TERT-BUTYL-4-METHYLPHENOXIDE) is used as a co-catalyst for activating metallocene catalysts, which are essential in the polymerization of olefins. This application is crucial for the production of polyolefins and other polymers, enhancing the efficiency and effectiveness of the polymerization process.
Used in Specialty Chemicals Manufacturing:
In the specialty chemicals industry, METHYLALUMINUM BIS(2,6-DI-TERT-BUTYL-4-METHYLPHENOXIDE) is utilized as a component in the synthesis of various high-performance materials. Its unique properties contribute to the development of advanced materials with specific characteristics required for specialized applications.
Used in High-Performance Materials Production:
METHYLALUMINUM BIS(2,6-DI-TERT-BUTYL-4-METHYLPHENOXIDE) is also employed in the production of high-performance materials, where its reactivity and stability are leveraged to create materials with superior properties for use in demanding applications.

InChI:InChI=1/2C15H24O.CH3.Al/c2*1-10-8-11(14(2,3)4)13(16)12(9-10)15(5,6)7;;/h2*8-9,16H,1-7H3;1H3;/q;;;+2/p-2/r2C15H24O.CH3Al/c2*1-10-8-11(14(2,3)4)13(16)12(9-10)15(5,6)7;1-2/h2*8-9,16H,1-7H3;1H3/q;;+2/p-2

Upstream product

• 128-37-0 2,6-di-tert-butyl-4-methyl-phenol 
• 75-24-1 trimethylaluminum 
• 41866-82-4 2,6-di-t-butyl-4-methylphenol anionic form 

Downstream Products

• 86803-85-2 dimethylaluminum 2,6-di-tert-butyl-4-methylphenoxide 
• 54644-43-8 2,2-Dimethyl-propionic acid 2,6-di-tert-butyl-4-methyl-phenyl ester 

Relevant academic research and scientific papers

Selective Separation of Structurally or Electronically Similar Ethers with MAD

Selective separation of the less hindered or electronically more labile of two different ethers has been accomplished with exceptionally bulky, Lewis acidic MAD by the yield of precipitates as selective Lewis acid-base complexes.

Extraction of Reliable Molecular Information from Diffusion NMR Spectroscopy: Hydrodynamic Volume or Molecular Mass?

Measuring accurate translational self-diffusion coefficients (Dt) by NMR techniques with modern spectrometers has become rather routine. In contrast, the derivation of reliable molecular information therefrom still remains a nontrivial task. In this paper, two established approaches to estimating molecular size in terms of hydrodynamic volume (VH) or molecular weight (M) are compared. Ad hoc designed experiments allowed the critical aspects of their application to be explored by translating relatively complex theoretical principles into practical take-home messages. For instance, comparing the Dt values of three isosteric Cp2MCl2 complexes (Cp=cyclopentadienyl, M=Ti, Zr, Hf), having significantly different molecular mass, provided an empirical demonstration that VH is the critical molecular property affecting Dt. This central concept served to clarify the assumptions behind the derivation of Dt=?(M) power laws from the Stokes–Einstein equation. Some pitfalls in establishing log (Dt) versus log (M) linear correlations for a set of species have been highlighted by further investigations of selected examples. The effectiveness of the Stokes–Einstein equation itself in describing the aggregation or polymerization of differently shaped species has been explored by comparing, for example, a ball-shaped silsesquioxane cage with its cigar-like dimeric form, or styrene with polystyrene macromolecules.

Phenoxide and alkoxide complexes of Mg, Al and Zn, and their use for the ring-opening polymerization of ?-caprolactone with initiators of different natures

A new packing polymorph of bis(2,6-di-tert-butyl-4-methylphenolato-κO)bis(tetrahydrofuran-κO)magnesium, [Mg(C15H23O)2(C4H8O)2] or Mg(BHT)2(THF)2, (BHT is the 2,6-di-tert-butyl-4-methylphenoxide anion and THF is tetrahydrofuran), (1), has the same space group (P21) as the previously reported modification [Nifant'ev et al. (2017d). Dalton Trans.46, 12132–12146], but contains three crystallographically independent molecules instead of one. The structure of (1) exhibits rotational disorder of the tert-butyl groups and positional disorder of a THF ligand. The complex of bis(2,6-di-tert-butyl-4-methylphenolato-κO)bis(μ2-ethyl glycolato-κ2O,O′:κO)dimethyldialuminium, [Al2(CH3)2(C4H7O3)2(C15H23O)2] or [(BHT)AlMe(OCH2COOEt)]2, (2), is a dimer located on an inversion centre and has an Al2O2 rhomboid core. The 2-ethoxy-2-oxoethanolate ligand (OCH2COOEt) displays a μ2-κ2O,O′:κO semi-bridging coordination mode, forming a five-membered heteronuclear Al–O–C–C–O ring. The same ligand exhibits positional disorder of the terminal methyl group. The redetermined structure of the heptanuclear complex octakis(μ3-benzyloxo-κO:κO:κO)hexaethylheptazinc, [Zn7(C2H5)6(C7H7O)8] or [Zn7(OCH2Ph)8Et6], (3), possesses a bicubic Zn7O8 core located at an inversion centre and demonstrates positional disorder of one crystallographically independent phenyl group. Cambridge Structural Database surveys are given for complexes structurally analogous to (2) and (3). Complexes (2) and (3), as well as derivatives of (1), are of interest as catalysts for the ring-opening polymerization of ?-caprolactone, and polymerization results are reported.

Sterically hindered aluminum alky is: Weakly interacting scavenging agents of use in olefin polymerization

Statically hindered aluminum methyl compounds derived from reaction of hindered phenols with AlMe3 (i.e., MeAl(BHT)2 and MeAl(BHT*)2; BHT = 2,6-di-te>t-butyl-4-methylphenoxide; BHT* = 2,4,6-triterf-butylphenoxide) are useful scavenging agents in olefin polymerization using metallocene catalysts. They do not, or only slowly, react with activators such as B(C6F5)3 or [Ph3C][B(C6F5)4] at 25 °C, nor do they coordinate to or react with metallocenium ion-pairs derived from metallocene dialkyls and these activators. A mixture of AlMe3 and a large excess of MeAl(BHT)2 proves advantageous for catalysts that are susceptible to reaction with BHT-H, the hydrolysis product of MeAl(BHT) 2. Ethylene polymerization experiments establish that the activity of [Cp2ZrMe][MeB(C6F5)3] is only slightly inhibited by AlMe3 in the presence of a significant excess of MeAl(BHT)2. Spectroscopic studies have revealed that AlMe 3 is in equilibrium with MeAl(BHT)2, forming Me 2Al(BHT). At low temperature using 13C NMR spectroscopy, a 1:1 mixture of AlMe3 and MeAl(BHT)2 is shown to consist of Al2Me6, MeAl(BHT)2, and primarily Me 2Al(M-BHT)2AlMe2. A higher temperature, both intra- and intermolecular exchange of both Al-Me and Al-BHT groups, coupled with the temperature dependence of the various equilibria involved, lead to 1H and 13C NMR spectra that are consistent with monomeric Me2Al(BHT). 1H and 19F NMR spectroscopic studies of mixtures of the ion-pairs [Me2C(Cp)IndMMe][MeB(C 6Fs)3] (M = Zr, Hf) or [Me2SiCp 2ZrMe][MeB(C6F5)3] with various quantities of AlMes in the presence of MeAl(BHT)2 were conducted. The AlMe3-mediated degradation of ion-pairs that are susceptible to B(CeF5)3 dissociation is largely absent in the presence of excess MeAl(BHT)2, although reversible formation of [Me 2SiCp2Zr(μ-Me)2AlMe2][MeB(C 6F5)3] and related adducts is observed at low ratios of MeAl(BHT)2 to AlMe3.

C7 SUBSTITUTED OXYSTEROLS AND METHODS AS NMDA MODULATORS

Compounds are provided according to Formula (A): and pharmaceutically acceptable salts thereof, and pharmaceutical compositions thereof; wherein R1A, R1B, n, R2A, R2B, R3, and R4 are as def

Switchable Synthesis of Z-Homoallylic Boronates and E-Allylic Boronates by Enantioselective Copper-Catalyzed 1,6-Boration

The enantioselective Cu-catalyzed 1,6-boration of (E,E)-α,β,γ,δ-unsaturated ketones is described, which gives homoallylic boronates with high enantiomeric purity and unexpectedly high Z-selectivity. By changing the solvent, the outcome can be altered to give E-allylic boronates.

NEUROACTIVE STEROIDS AND METHODS OF USE THEREOF

3beta, 17beta disubstituted steroidal compounds, pharmaceutically acceptable salts thereof, and pharmaceutical compositions thereof, are provided for the prevention and treatment of a variety of CNS-related conditions.

Stereoselective synthesis of chiral piperidine derivatives employing arabinopyranosylamine as the carbohydrate auxiliary

Stereoselective synthesis of 2-substituted dehydropiperidinones and their further transformation to variously disubstituted piperidine derivatives was achieved employing D-arabinopyranosylamine as the stereodifferentiating carbohydrate auxiliary. A domino Mannich-Michael reaction of 1-methoxy-3-(trimethylsiloxy)butadiene (Danishefsky's diene) with O-pivaloylated arbinosylaldimines furnished N-arabinosyl dehydropiperidinones in high diastereoselectivity. Subsequent conjugate cuprate addition gave 2,6-cis-substituted piperidinones, while enolate alkylation furnished 2,3-trans-substituted dehydropiperidinones. Electrophilic substitution at the enamine structure afforded 5-nitro- and 5-halogen dehydropiperidinones of which the latter were applied in palladium-catalyzed coupling reactions. The absolute configuration of the obtained products was proven by NMR and X-ray structure analysis as well as by syntheses of the alkaloids (+)-coniine and (+)-dihydropinidine.

Bulky aluminum alkyl scavengers in olefin polymerization with group 4 catalysts

The binding of H2O to MeAl(OAr)2 (1: Ar = 2,6-di-tert-butyl-4-methylphenyl) in THF-d8 at -40 °C provides aquo complex 2, the structure of which was determined by X-ray crystallography. Complex 2 is unstable above 0 °C in THF-d8 and decomposes to form ArOH (major), CH4 (minor), and a methyl aluminoxane of undetermined structure. Decomposition of 2 follows first-order kinetics with k = 3.0 × 10-4 s-1 at 5 °C. The hindered phenol ArOH slowly reacts with [Cp2ZrMe][MeB(C6F5)3] (4) in bromobenzene-d5 solution at 25 °C to furnish CH4 and [Cp2ZrOAr][MeB(C6F5)3] (5), the structure of which was confirmed by X-ray crystallography. This reaction follows second-order kinetics for [ArOH] = [4] = 0.045 M and with k = 2.8 × 10-3 M-1 s-1 at 25 °C. This corresponds to a rate that is >107 × slower than the apparent rate of ethylene insertion for 4 at 25 °C at typical concentrations encountered in olefin polymerization. The kinetic data, as well as control experiments involving the addition of ArOH to active catalyst producing poly(ethylene), demonstrate that ArOH has essentially no effect on polymerization kinetics involving 4. Copyright

Towards an understanding of the conjugate addition of organolithium reagents to α,β-unsaturated ketones: The isolation and solid-state structure of a monomeric lithium aluminate with very short agostic LiHC interactions1

Reaction of methylaluminium bis(2,6-di-tert-butyl-4-methylphenoxide) (MAD), 1, with alkyllithium reagents, R′Li (R′=Me, n-Bu or t-Bu), yields the solvent-dependent products lithium bis(2,6-di-tert-butyl-4-methylphenoxide)-THF complex, 2·THF, lithium dimethylbis(2,6-di-tert-butyl-4-methylphenoxide)aluminate, 3, a new type of lithium aluminate in which the lithium centre is stabilised by very short agostic LiH(t-Bu) interactions, and tris(alkyl)aluminium. The observation of these products suggests an explanation for the tendency of α,β-unsaturated ketones to undergo conjugate (rather than 1,2-) addition in the presence of MAD and organolithium reagents.