2516-69-0

Upstream product

• 917-64-6 methyl magnesium iodide 
• 487-68-3 mesytaldehyde 
• 1667-01-2 2,4,6-Trimethylacetophenone 
• 1517-71-1 1-mesitylethanol 
• 97-72-3 2-Methylpropionic anhydride 
• 769-25-5 2,4,6-trimethylstyrene 
• 123-62-6 propionic acid anhydride 
• 75-07-0 acetaldehyde 
• 2633-66-1 2-mesitylmagnesium bromide 
• 64-17-5 ethanol 
• 108-67-8 1,3,5-trimethyl-benzene 
• 25015-63-8 4,4,5,5-tetramethyl-[1,3,2]-dioxaboralane 
• 108-24-7 acetic anhydride 
• 98-88-4 benzoyl chloride 

Downstream Products

• 51270-90-7 (R)-1-chloro-1-mesityl-ethane 
• 86561-29-7 acetic acid-(1-mesityl-ethyl ester) 
• 3982-67-0 ethylmesitylene 
• 1517-71-1 (S)-1-(2,4,6-trimethylphenyl)ethanol 
• 2516-69-0 (R)-1-mesitylethanol 
• 84194-77-4 Acetic acid (S)-1-(2,4,6-trimethyl-phenyl)-ethyl ester 
• 934631-25-1 rac-3-(3-pyridine)propionic acid 1-mesityl-ethyl ester 
• 1667-01-2 2,4,6-Trimethylacetophenone 
• 1028432-18-9 C₂₄H₃₇NO₃SSi 
• 1268070-61-6 (S)-1-mesitylethyl isobutyrate 
• 103845-62-1 (1Z)-1-mesitylethanone oxime 
• 107626-95-9 3-phenyl-1-(2,4,6-trimethylphenyl)-1-propanone 
• 6332-04-3 3-phenyl-1-(2,4,6-trimethylphenyl)-2-propen-1-one 
• 111357-65-4 (+/-)-phthalic acid mono-(1-mesityl-ethyl ester) 

Relevant academic research and scientific papers

Hydrosilylation of Aldehydes and Ketones Catalyzed by a 2-Iminopyrrolyl Alkyl-Manganese(II) Complex

A well-defined and very active single-component manganese(II) catalyst system for the hydrosilylation of aldehydes and ketones is presented. First, the reaction of 5-(2,4,6-iPr3C6H2)-2-[N-(2,6-iPr2C6H3)formimino]pyrrolyl potassium (KL) and [MnCl2(Py)2] afforded the binuclear 2-iminopyrrolyl manganese(II) pyridine chloride complex [Mn2{κ2N,N′-5-(2,4,6-iPr3C6H2)-NC4H2-2-C(H)═N(2,6-iPr2C6H3)}2(Py)2(μ-Cl)2] 1. Subsequently, the alkylation reaction of complex 1 with LiCH2SiMe3 afforded the respective (trimethylsilyl)methyl-Mn(II) complex [Mn{κ2N,N′-5-(2,4,6-iPr3C6H2)-NC4H2-2-C(H)═N(2,6-iPr2C6H3)}(Py)CH2SiMe3] 2 in a good yield. Complexes 1 and 2 were characterized by elemental analysis, 1H NMR spectroscopy, Evans' method, FTIR spectroscopy, and single-crystal X-ray diffraction. While the crystal structure of complex 1 has been identified as a binuclear entity, in which the Mn(II) centers present pentacoordinate coordination spheres, that of complex 2 corresponds to a monomer with a distorted tetrahedral coordination geometry. Complex 2 proved to be a very active precatalyst for the atom-economic hydrosilylation of several aldehydes and ketones under very mild conditions, with a maximum turnover frequency of 95 min-1, via a silyl-Mn(II) mechanistic route, as asserted by a combination of experimental and theoretical efforts, the respective silanes were cleanly converted to the respective alcoholic products in high yields.

Half-Sandwich Nickel(II) NHC-Picolyl Complexes as Catalysts for the Hydrosilylation of Carbonyl Compounds: Evidence for NHC-Nickel Nanoparticles under Harsh Reaction Conditions

The cationic [NiCp(Mes-NHC-CH2py]Br complex 2 a was prepared directly by the reaction of nickelocene with 1-(2-picolyl)-3-mesityl-imidazolium bromide (1), and its PF6? derivative 2 b, by subsequent salt metathesis. X-ray diffraction studies and Variable Temperature 1H NMR experiments run with 2 a and 2 b strongly suggest the bidentate coordination of the picolyl-functionalized carbene to the nickel both in the solid state and in solution in both cases. These data suggest the absence of hemilabile behavior of the latter, even in the presence of a coordinating anion. Both complexes show similar activity in aldehyde hydrosilylation, further implying the absence of hemilability of the picolyl-functionalized carbene, and effectively reduce a broad scope of aldehydes in the absence of additive under mild conditions. In the case of ketones, effective hydrosilylation is only observed in the presence of a catalytic amount of potassium t-butoxide at 100 °C. Dynamic light scattering, scanning transmission electron microscopy and X-ray photoelectron spectroscopy show evidence for the involvement of NHC-picolyl-Ni nanoparticles under these conditions.

Borohydride intermediates pave the way for magnesium-catalysed enantioselective ketone reduction

A magnesium precatalyst for the highly enantioselective hydro-boration of CO bonds is reported. The mechanistic basis of the unprecedented selectivity of this transformation has been investi-gated experimentally by isolation of catalytic intermediates and theoretically by DFT calculations. The facile formation of a magnesium borohydride species is critical in overcoming competing pathways in the selectivity-determining insertion step.

Palladium-Catalyzed Selective Reduction of Carbonyl Compounds

Two new examples of structurally characterized β-diketiminate analogues i.e., conjugated bis-guanidinate (CBG) supported palladium(II) complexes, [LPdX]2; [L= {(ArHN)(ArN)–C=N–C=(NAr)(NHAr)}; Ar = 2,6-Et2-C6H3], X = Cl (1), Br (2) have been reported. The synthesis of complexes 1–2 was achieved by two methods. Method A involves deprotonation of LH by nBuLi followed by the treatment of LLi (insitu formed) with PdCl2 in THF, which afforded compound 1 in good yield (75 %). In Method B, the reaction between free LH and PdX2 (X = Cl or Br) in THF allowed the formation of complexes 1 (Yield 73 %) and 2 (Yield 52 %), respectively. Moreover, these complexes were characterized thoroughly by several spectroscopic techniques (1H, 13C NMR, UV/Vis, FT-IR, and HRMS), including single-crystal X-ray structural and elemental analyses. In addition, we tested the catalytic activity of these complexes 1–2 for the hydroboration of carbonyl compounds with pinacolborane (HBpin). We observed that compound 1 exhibits superior catalytic activity when compared to 2. Compound 1 efficiently catalyzes various aldehydes and ketones under solvent-free conditions. Furthermore, both inter- and intramolecular chemoselectivity hydroboration of aldehydes over other functionalities have been established.

Benzimidazole fragment containing Mn-complex catalyzed hydrosilylation of ketones and nitriles

The synthesis of a new bidentate (NN)–Mn(I) complex is reported and its catalytic activity towards the reduction of ketones and nitriles is studied. On comparing the reactivity of various other Mn(I) complexes supported by benzimidazole ligand, it was observed that the Mn(I) complexes bearing 6-methylpyridine and benzimidazole fragments exhibited the highest catalytic activity towards monohydrosilylation of ketones and dihydrosilylation of nitriles. Using this protocol, a wide range of ketones were selectively reduced to the corresponding silyl ethers. In case of unsaturated ketones, the chemoselective reduction of carbonyl group over olefinic bonds was observed. Additionally, selective dihydrosilylation of several nitriles were also achieved using this complex. Mechanistic investigations with radical scavengers suggested the involvement of radical species during the catalytic reaction. Stoichiometric reaction of the Mn(I) complex with phenylsilane revealed the formation of a new Mn(I) complex.

Bottleable NiCl2(dppe) as a catalyst for the Markovnikov-selective hydroboration of styrenes with bis(pinacolato)diboron

Although transition-metal-catalysed hydroboration reactions of alkenes have been extensively studied, only three examples using Ni complexes have been reported so far. In this study, we have examined hydroboration reactions of alkenes using Ni/phosphine complexes. The commercially available and bottleable complex NiCl2(dppe) (dppe = 1,2-bis(diphenylphosphino)ethane) serves as a catalyst for the highly Markovnikov-selective hydroboration of styrene derivatives that affords the desired Markovnikov products in high yield.

Phosphine-NHC Manganese Hydrogenation Catalyst Exhibiting a Non-Classical Metal-Ligand Cooperative H2 Activation Mode

Deprotonation of the MnI NHC-phosphine complex fac-[MnBr(CO)3(κ2P,C-Ph2PCH2NHC)] (2) under a H2 atmosphere readily gives the hydride fac-[MnH(CO)3(κ2P,C-Ph2PCH2NHC)] (3) via the intermediacy of the highly reactive 18-e NHC-phosphinomethanide complex fac-[Mn(CO)3(κ3P,C,C-Ph2PCHNHC)] (6 a). DFT calculations revealed that the preferred reaction mechanism involves the unsaturated 16-e mangana-substituted phosphonium ylide complex fac-[Mn(CO)3(κ2P,C-Ph2P=CHNHC)] (6 b) as key intermediate able to activate H2 via a non-classical mode of metal-ligand cooperation implying a formal λ5-P–λ3-P phosphorus valence change. Complex 2 is shown to be one of the most efficient pre-catalysts for ketone hydrogenation in the MnI series reported to date (TON up to 6200).

Asymmetric Hydrogenation of Polysubstituted Aromatic Ketones Catalyzed by the DIPSkewphos/PICA Derivative–Ruthenium(II) Complexes

The DIPSkewphos/PICA derivative-Ru(II) complexes catalyzed asymmetric hydrogenation of significantly sterically hindered 2’,3’,4’,5’,6’-pentamethylacetophenone, which was not reduced with NaBH4 at 25 °C, with a substrate-to-catalyst molar ratio

Constructing reactive Fe and Co complexes from isolated picolyl-functionalized N-heterocyclic carbenes

We report the isolation of free picolyl-functionalized N-heterocyclic carbenes (NHCs), which serve as versatile precursors to access low coordinate iron and cobalt complexes. The reactivities of these new iron and cobalt complexes towards catalytic hydrosilylation of ketones have also been explored. For example, low loadings (0.05-1 mol%) of a four-coordinate iron complex bearing two deprotonated picolyl-NHC ligands can effect the fast catalytic reduction of ketones using the inexpensive industrial byproduct polymethylhydrosiloxane (PMHS) as the reductant at ambient temperature.

Carbonyl and ester C-O bond hydrosilylation using κ4-diimine nickel catalysts

The synthesis of alkylphosphine-substituted α-diimine (DI) ligands and their subsequent addition to Ni(COD)2 allowed for the preparation of (iPr2PPrDI)Ni and (tBu2PPrDI)Ni. The solid state structures of both compounds were found to feature a distorted tetrahedral geometry that is largely consistent with the reported structure of the diphenylphosphine-substituted variant, (Ph2PPr DI)Ni. To explore and optimize the synthetic utility of this catalyst class, all three compounds were screened for benzaldehyde hydrosilylation activity at 1.0 mol% loading over 3 h at 25 °C. Notably, (Ph2PPr DI)Ni was found to be the most efficient catalyst while phenyl silane was the most effective reductant. A broad scope of aldehydes and ketones were then hydrosilylated, and the silyl ether products were hydrolyzed to afford alcohols in good yield. When attempts were made to explore ester reduction, inefficient dihydrosilylation was noted for ethyl acetate and no reaction was observed for several additional substrates. However, when an equimolar solution of allyl acetate and phenyl silane was added to 1.0 mol% (Ph2PPr DI)Ni, complete ester C-O bond hydrosilylation was observed within 30 min at 25 °C to generate propylene and PhSi(OAc)3. The scope of this reaction was expanded to include six additional allyl esters, and under neat conditions, turnover frequencies of up to 990 h-1 were achieved. This activity is believed to be the highest reported for transition metal-catalyzed ester C-O bond hydrosilylation. Proposed mechanisms for (Ph2PPr DI)Ni-mediated carbonyl and allyl ester C-O bond hydrosilylation are also discussed.