77256-41-8

Upstream product

• 57199-00-5 2,4,6-triisopropylbenzoyl chloride 
• 100-51-6 benzyl alcohol 
• 49623-71-4 2,4,6-triisopropylbenzoic acid 
• 21524-34-5 2,4,6-triisopropyl-1-bromobenzene 
• 100-39-0 benzyl bromide 
• 108-88-3 toluene 

Downstream Products

• 77256-62-3 1'-methylbenzyl 2,4,6-triisopropylbenzoate 

Relevant academic research and scientific papers

Esterification of the Primary Benzylic C-H Bonds with Carboxylic Acids Catalyzed by Ionic Iron(III) Complexes Containing an Imidazolinium Cation

The first iron-catalyzed esterification of the primary benzylic C-H bonds with carboxylic acids using di-tert-butyl peroxide as an oxidant is achieved by novel ionic iron(III) complexes containing an imidazolinium cation. The use of well-defined, air-stable, and available iron(III) complex in a 5 mol % loading and readily available starting materials with a broad generality and outstanding sterically hindered tolerance renders this methodology a useful alternative to other protocols that are typically employed for the synthesis of benzyl esters.

Enantioselective synthesis of α-phenyl- and α-(dimethylphenylsilyl)alkylboronic esters by ligand mediated stereoinductive reagent-controlled homologation using configurationally labile carbenoids

Chain extension of boronic esters by the action of configurationally labile racemic lithium carbenoids in the presence of scalemic bisoxazoline ligands was explored for the enantioselective synthesis of the two title product classes. Enantioenriched 2° carbinols generated by oxidative work-up (NaOOH) of initial α-phenylalkylboronate products were obtained in 35-83% yield and 70-96% ee by reaction of B-alkyl and B-aryl neopentyl glycol boronates with a combination of O-(α-lithiobenzyl)-N,N-diisopropylcarbamate and ligand 3,3-bis[(4S)-4,5-dihydro-4-isopropyloxazol-2-yl] pentane in toluene solvent (-78 °C to rt) with MgBr2·OEt2 additive. Enantioenriched α-(dimethylsilylphenylsilyl)alkylboronates were obtained in 35-69% yield and 9-57% ee by reaction of B-alkyl pinacol boronates with a combination of lithio(dimethylphenylsilyl)methyl 2,4,6-triisopropylbenzoate and ligand 2,2-bis[(4S)-4,5-dihydro-4-isopropyloxazol-2-yl]propane in cumene solvent (-45 °C to -95 °C to rt). The stereochemical outcome of the second type of reaction depended on the temperature history of the organolithium·ligand complex indicating that the stereoinduction mechanism in this case involves some aspect of dynamic thermodynamic resolution. This journal is

A relative organolithium stability scale derived from tin-lithium exchange equilibria. Substituent effects on the stability of α-oxy- and α-aminoorganolithium compounds

Quantitative thermodynamic stability scales of organolithium compounds can be derived from measurements of tin-lithium exchange equilibria. A ΔGeq scale of α-oxy- and α-aminoorganolithium compounds was established, and quantitative stabilization effects of O-alkyl, O-alkoxyalkyl, O-carbamoyl, N-carbamoyl, and O-carbonyl groups of the α-carbanion are presented. It has been found that an α-oxycarbanion is far better stabilized by a carbonyl group as the O-substituent than by an alkyl or alkoxyalkyl group, while the anion-stabilizing effects of the different O-carbonyl substituents are comparable. An N-carbamoyl group was found to have a somewhat higher stabilizing effect than its O-carbamoyl counterpart. NMR data are presented that show that benzylic N- or O-substituted carbanions have highly planarized structures where the negative charge is highly delocalized. The stability data obtained from the tin-lithium exchanges can be easily converted into "effective pK" data that are useful for predicting the acid-base behavior of this type of organolithium species.

Dipole-Stabilized Carbanions from Esters: α-Oxo Lithiations of 2,6-Substituted Benzoates of Primary Alcohols

The synthetic utility of dipole-stabilized carbanions from esters is illustrated by the preparations, α-oxo lithiations, electrophilic substitutions, and cleavages of the 2,4,6-triisopropylbenzoates and the 2,6-bis(dimethylamino)-3,5-diisopropylbenzoates of primary alcohols, 2 and 3, respectively.Typical electrophiles used in this methodology include primary alkyl halides, aldehydes, ketones, trimethylsilyl chloride, and tri-n-butyltin chloride.Cleavages of the substituted esters of 2 are accomplished with lithium aluminum hydride while hydrolyses of derivatives of3 can be achieved under acidic conditions.The 2,6-substitutions of 2 and 3 are considered to enforce orthogonality of the carbonyl group and the phenyl ring and thereby to inhibit addition to the carbonyl by the organolithium base used for the metalation by placing the substituents in the trajectory for nucleophilic addition along the LUMO of the carbonyl.The acidic hydrolysis of 3 under conditions where 2 is stable is attributed to protonation of the dimethylamino group which provides subsequent assistance for nucleophilic addition.These metalations provide the key steps in the preparation of secondary α-lithio alcohol synthetic equivalents from primary alcohols.Lithiation of 1'-methylbenzyl 2,4,6-triisopropylbenzoate proceeds α to oxygen as expected, but attempts to prepare analogous unactivated tertiary α-lithio esters were unsuccessful.The lithiation of 2'-methoxyethyl 2,4,6-triisopropylbenzoate is followed by elimination of methoxide and α-oxo metalation of the resulting vinyl ester.Lithiation of allyl 2,4,6-triisopropylbenzoate provides 1-(2,4,6-triisopropylphenyl)-1,2-butanedione by rearrangement.