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Upstream product

• 150-76-5 4-methoxy-phenol 

Downstream Products

• 2369-11-1 5-fluoro-2-nitroaniline 
• 189214-30-0 4-(4-methoxyphenoxy)-2-fluoro-nitrobenzene 
• 189214-39-9 2-(4-methoxyphenoxy)-4-fluoro-nitrobenzene 
• 1075165-90-0 Cp^*Ti(OC₆H₄-4-(OMe))Me₂ 
• 227951-93-1 (R)-1-(hex-1-en-3-yloxy)-4-methoxybenzene 
• 20973-10-8 2-hydroxy-5-methoxy-N-phenyl-benzamide 

Relevant academic research and scientific papers

Thermochemical investigation of the oxygenation of vitamin K

Discovery of a new oxygenation reaction of naphthohydroquinone anions makes possible a determination of the heat of reaction (ΔHox) of oxygen with the potassium salt derived from deprotonation of the hydroquinone form of vitamin K. From that value (-33.52 ± 0.60 kcal/mol), the heat of deprotonation of vitamin KH2 (-30.03 ± 1.20 kcal/mol), and the heat of deprotonation of water (-6.05 ± 0.3 kcal/mol), the enthalpy change for converting vitamin KH2 to vitamin K oxide is established to be -57.5 kcal/mol, in reasonable agreement with our previous estimate of -62.4 kcal/mol for the oxygenation of the parent naphthohydroquinone. Indeed, in similar fashion the heat of oxygenation of the parent naphthohydroquinone was determined to be -58.47 kcal/mol, and this permits the assignment of a heat of formation to naphthoquinone epoxide of ΔHf° = -47.6 kcal/mol. Heats of oxygenation and deprotonation of a variety of related phenols and naphthols provide perspective on cation and substitution effects. These data provide strong support for the base strength amplification mechanism for the biological action of vitamin K proposed by two of us (P.D. and S.W.H.).

Direct catalytic asymmetric vinylogous conjugate addition of unsaturated butyrolactones to α,β-unsaturated thioamides

Soft Lewis acid/Bronsted base cooperative catalysts have enabled direct catalytic asymmetric vinylogous conjugate addition of α,β- and β,γ-unsaturated butyrolactones to α,β-unsaturated thioamides with perfect atom economy. When using α-angelica lactone and its derivatives as pronucleophiles, as little as 0.5 mol % catalyst loading was sufficient to complete the reaction necessary to construct consecutive tri- and tetrasubstituted stereogenic centers in a highly diastereo- and enantioselective fashion. Soft spot: Soft Lewis acid/Bronsted base cooperative catalysts have enabled the title reaction of α,β- and β,γ- unsaturated butyrolactones with perfect atom economy. When using α-angelica lactone and its derivatives as pronucleophiles, a 0.5 mol % catalyst loading was sufficient to complete the reaction to construct consecutive tri- and tetrasubstituted stereogenic centers in a highly diastereo- and enantioselective fashion.

A designed amide as an aldol donor in the direct catalytic asymmetric aldol reaction

The direct catalytic asymmetric aldol reaction offers efficient access to β-hydroxy carbonyl entities. Described is a robust direct catalytic asymmetric aldol reaction of α-sulfanyl 7-azaindolinylamide, thus affording both aromatic and aliphatic β-hydroxy amides with high ee values. The design of this transformation features a cooperative interplay of a soft and a hard Lewis acid, which together facilitate the challenging chemoselective enolization by a hard Bronsted base.

Direct catalytic asymmetric addition of allyl cyanide to ketones via soft lewis acid/hard bronsted base/hard lewis base catalysis

We report that a hard Lewis base substantially affects the reaction efficiency of direct catalytic asymmetric γ-addition of allyl cyanide (1a) to ketones promoted by a soft Lewis acid/hard Bronsted base catalyst. Mechanistic studies have revealed that Cu/(R,R)-Ph-BPE and Li(OC 6H4-p-OMe) serve as a soft Lewis acid and a hard Bronsted base, respectively, allowing for deprotonative activation of 1a as the rate-determining step. A ternary catalytic system comprising a soft Lewis acid/hard Bronsted base and an additional hard Lewis base, in which the basicity of the hard Bronsted base Li(OC6H4-p-OMe) was enhanced by phosphine oxide (the hard Lewis base) through a hard-hard interaction, outperformed the previously developed binary soft Lewis acid/hard Bronsted base catalytic system, leading to higher yields and enantioselectivities while using one-tenth the catalyst loading and one-fifth the amount of 1a. This second-generation catalyst allows efficient access to highly enantioenriched tertiary alcohols under nearly ideal atom-economical conditions (0.5-1 mol % catalyst loading and a substrate molar ratio of 1:2).

Proton affinities and aggregation states of lithium alkoxides, phenolates, enolates, β-dicarbonyl enolates, carboxylates, and amidates in tetrahydrofuran

The proton affinities of the title compounds are represented by their heats of deprotonation, ΔHdep, through reactions with lithium bis(trimethylsilyl)amide, LiHMDS, in tetrahydrofuran at 25°C. Aggregation numbers of the parent acid and of its lithium salt at a concentration of 0.10 M were obtained by vapor-pressure osmometry at 37°C. Lithium phenolates were also studied by conductivity at 25°C. ΔHdeps for 27 oxygen, nitrogen, and carbon acids of varied types correlate fairly well (R = 0.95) with their published pKas in dimethyl sulfoxide although their degrees of aggregation in THF vary from one to over seven. In some cases, the ΔHdep of an acid is strongly dependent on the concentration ratio of LiHMDS to that of the acid's lithium salt at the time of measurement. Aggregation numbers determined by VPO in this report agree with available published values obtained by previous workers using several techniques. There is no obvious relationship between the aggregation number of the lithium salt and the basicity of the corresponding anion as represented by ΔHdep. This observation along with independent evidence for equilibria between monomers, dimers, tetramers, etc. for a number of compounds indicate that there are only small differences between the relative stabilities of different aggregation states. Conductance data for lithium p-nitrophenolate were treated by Wooster analysis, the results of which suggest equilibria between ion triplets, ion pairs, and free ions in THF. The conductance of LiHMDS in this solvent is surprisingly high, and this property was used to demonstrate an interaction between LiHMDS and lithium o-tert-butylphenolate.