6860-93-1

Upstream product

• 7228-47-9 2-(2-naphthyl)ethanol 
• 93-97-0 benzoic acid anhydride 
• 98-88-4 benzoyl chloride 
• 27544-18-9 (S)-1-(2-Naphthyl)ethanol 
• 939-27-5 2-ethylnaphthalene 
• 100-52-7 benzaldehyde 
• 65-85-0 benzoic acid 

Relevant academic research and scientific papers

Size-Driven Inversion of Selectivity in Esterification Reactions: Secondary Beat Primary Alcohols

Relative rates for the Lewis base-mediated acylation of secondary and primary alcohols carrying large aromatic side chains with anhydrides differing in size and electronic structure have been measured. While primary alcohols react faster than secondary ones in transformations with monosubstituted benzoic anhydride derivatives, relative reactivities are inverted in reactions with sterically biased 1-naphthyl anhydrides. Further analysis of reaction rates shows that increasing substrate size leads to an actual acceleration of the acylation process, the effect being larger for secondary as compared to primary alcohols. Computational results indicate that acylation rates are guided by noncovalent interactions (NCIs) between the catalyst ring system and the DED substituents in the alcohol and anhydride reactants. Thereby stronger NCIs are formed for secondary alcohols than for primary alcohols.

Kinetic resolution of sterically hindered secondary alcohols catalyzed by aminophosphinite organocatalyst

Kinetic resolution of secondary alcohols by benzoylation using a phosphinite derivative of (1S,2R)-1-amino-2-indanol as the catalyst was investigated. The aminophosphinite catalyst is effective for the kinetic resolution of aryl cycloalkyl carbinols with a small number of examples for organocatalytic kinetic resolution to achieve resolution with s = up to 44. Although the benzoylation of phenylalkanols proceeded with a low selectivity, 1-arylalkanols bearing at least one substituent at the ortho position on the benzene ring or a branched alkyl group on the carbinol carbon were resolved with acceptable selectivity.

Bu4NI-catalyzed benzylic acyloxylation of alkylarenes with aromatic aldehydes

An nBu4NI-catalyzed benzylic C-H acyloxylation of alkylarenes with readily available aromatic aldehydes has been developed. These reactions occur under mild and clean reaction conditions using tert-butyl hydroperoxide as the green terminal oxid

A highly enantioselective phosphabicyclooctane catalyst for the kinetic resolution of benzylic alcohols

A new class of chiral phosphines belonging to the P-aryl-2-phosphabicyclo[3.3.0]octane family (PBO) has been prepared by enantioselective synthesis starting from lactate esters and 2,2-dimethylcy-clopentanone enolate 5. A selective enolate alkylation method has been developed for preparation of 9 and 10 using a chelating ester substituent in the triflate alkylating agent 11. Subsequent conversion to the PBO catalysts 2 and 39 relies on a diastereoselective cyclization from the cyclic sulfate 17 and LiPHAr to afford the more hindered endo-aryl phosphines. These phosphines function as efficient catalysts for the kinetic resolutions of aryl alkyl carbinols by benzoylation (16, 21, 22) or iso-butyroylation in the case of the less hindered aryl alkyl carbinol substrates. With o-substituted aryl alkyl carbinols, the enantioselectivities exceed 100, and s = 380 ± 10 has been demonstrated in the case of methyl mesityl carbinol. The PBO- catalyzed acylations probably involve a P-acylphosphonium carboxylate intermediate and a tightly ion paired transition state.

Secondary Benzylation Using Benzyl Alcohols Catalyzed by Lanthanoid, Scandium, and Hafnium Triflate

The combination of a secondary benzyl alcohol and a metal triflate (e.g., La, Yb, Sc, and Hf triflate) in nitromethane was a highly effective secondary-benzylation system. Secondary benzylation of carbon (aromatic compounds, olefins, an enol acetate), nitrogen (amide derivatives), and oxygen (alcohols) nucleophiles was carried out with a secondary benzyl alcohol and 0.01-1 mol % of a metal triflate in the presence of water. Secondary benzyl alcohols and nucleophiles bearing acid-sensitive functional groups (e.g., tert-butyldimethylsilyloxy and acetoxy groups and methyl and benzyl esters) could be used for alkylation. Hf(OTf)4 was the most active catalyst for this alkylation, and trifluoromethanesulfonic acid (triflic acid, TfOH) was also a good catalyst. The catalytic activity of metal triflates and TfOH increased in the order La(OTf)3 3 3 4. A mechanistic study was also performed. The reaction of 1-phenylethanol (4a) in the presence of Sc(OTf) 3 in nitromethane gave an equilibrium mixture of 4a and bis(1-phenylethyl) ether (54). Addition of a carbon nucleophile to the equilibrium mixture gave alkylated product in high yield.