Tert-butyl Benzoate Research Articles

Low-Density Unsaturated Polyester Resin with the Presence of Dual-Initiator.

Dual-initiation is a new orientation of many studies in the curing of unsaturated polyester resin and the manufacture of low-density unsaturated polyester resin (LDUPR) composite materials. In our research, two kinds of low-temperature (40-70 °C) initiators (cyclohexanone peroxide (CYHP) and methyl ethyl ketone peroxide (MEKP)), one kind of medium-temperature (70-130 °C) initiator (tert-butyl peroxy-2-ethylhexanoate (TBPO)), and three kinds of high-temperature (≥130 °C) initiators (tert-butyl benzoate peroxide (TBPB), tert-amyl carbonate peroxide-2-ethylhexanoate (TAEC), and tert-butyl carbonate peroxide-2-ethylhexanoate (TBEC)) were applied to constitute different dual-initiators. Those dual-initiators were a low-temperature dual-initiator (CYHP/MEKP), medium-low-temperature dual-initiators (CYHP/TBPO and MEKP/TBPO), and high-temperature dual-initiators (TAEC/TBPB, TAEC/TBEC, and TBEC/TBPB). In the low-temperature and medium-low-temperature ranges, the LDUPR sample displayed the highest specific compression strength (Ps) of 42.08 ± 0.26 MPa·g-1·cm3 in the presence of the MEKP/TBPO dual-initiator. In the high-temperature range, the LDUPR sample exhibited the highest specific compression strength (Ps) of 43.32 ± 0.45 MPa·g-1·cm3 for the existence of the TAEC/TBPB dual-initiator. It is pointed out that the dual-initiator released more active free radicals, accelerating the initial curing time and the peak time of UPR. More active free radicals caused both high-activity (short-chain) molecules and low-activity (long-chain or intertwined) molecules in resin to cross-link, prolonging UPR's curing process by approximately two minutes and resulting in an improvement of UPR's cross-linking. In the presence of a dual-initiator, the integrated and planar microstructure of LDUPR samples performed uniformly distributed dimples, dispersed external forces, and enhanced samples' specific compressive strength.

Revisiting the Mg/TMSCl/Dipolar Solvent System for Dearomatic Silylation of Aryl Carbonyl Compounds: Substrate Scope, Transformations, and Mechanistic Studies.

Dearomatic silylation of arene derivatives is an intriguing synthetic target, which represents an elegant extension of Birch reduction and produces silylated cyclohexene derivatives with great potential of further transformation. Herein, we report a systematic study on dearomatic silylation of aryl carbonyl compounds with Mg and the TMSCl/NMP adduct. The protocol displays a wide range of substrate scope, including alkyl aryl ketones, aromatic amides, benzonitriles, tert-butyl benzoates, and even 2,2'-bipyridines. Synthetic utility is demonstrated using the products as versatile substrate in various transformations. The detailed mechanism is presented with both control experimental analyses and theoretical calculations. An unusual five-coordinated silicon dianion intermediate is first proposed and described here. The selectivity is influenced by the relative rates of single electron reductions (the TMSCl/NMP adduct versus the substrate) and the steric effects.

An efficient synthesis of N-tert-butyl amides by the reaction of tert-butyl benzoate with nitriles catalyzed by Zn(ClO4)2·6H2O

An efficient, mild and inexpensive synthesis of N-tert-butyl amides from the reaction of nitriles (aryl, benzyl and sec-alkyl nitriles) with tert-butyl benzoate catalyzed by the employment of 2 mol% Zn(ClO4)2·6H2O at 50 °C under the solvent-free conditions is described. The reaction with aryl nitriles was carried out well and afforded the N-tert-butyl amides in 87–97% yields after 1 h. The benzyl and sec-alkyl nitriles also proceeded well and produced the N-tert-butyl amides in 83–91% yields after 5 h.

Discovery and structure-guided optimization of tert-butyl 6-(phenoxymethyl)-3-(trifluoromethyl)benzoates as liver X receptor agonists.

To obtain potent liver X receptor (LXR) agonists, a structure-activity relationship study was performed on a series of tert-butyl benzoate analogs. As the crystal structure analysis suggested applicable interactions between the LXR ligand-binding domain and the ligands, two key functional groups were introduced. The introduction of the hydroxyl group on the C6-position of the benzoate part enhanced the agonistic activity in a cell-based assay, and the carboxyl group in terminal improved the pharmacokinetic profile in mice, respectively. The obtained compound 32b increased blood ABCA1 mRNA expression without plasma TG elevation in both mice and cynomolgus monkeys.

Transition‐Metal‐Free Alkoxycarbonylation of Aryl Halides

Transitions: The title reaction has been developed for the synthesis of a variety of tert-butyl benzoates by employing 1,10-phenanthroline as an additive. Various functional groups were tolerated and heteroaryl iodides were also suitable substrates. Preliminary mechanism studies were conducted and indicate the participation of radical intermediates.

Cleavage of tert-Butyl Benzoates with NaH in DMF: Comments on the ­Mechanism and a Simple and Safe Alternative Procedure

The hazardous and inconvenient Schmidt procedure for tert-butyl benzoate ester cleavage by NaH in DMF has been reinvestigated. The reaction is suggested to involve B AC 2 ester cleavage, facilitated by adventitious, NaH-derived NaOH, rather than the proposed E2 elimination of isobutylene by DMF-derived NaNMe2. Powdered KOH in THF is a significantly safer and simpler alternative that effects cleavage of tert-butyl benozoates, at ambient temperature, in excellent yield (94-99%).

Di- tert-butyl dicarbonate: a versatile carboxylating reagent

Carbon nucleophiles generated by a non-nucleophilic base (LDA) were effectively trapped with di- tert-butyl dicarbonate (Boc-anhydride) to provide the corresponding tert-butyl aryl acetates, di- tert-butyl aryl malonates, unsymmetrical aryl malonates and tert-butyl benzoates in high yields. This reaction represents another useful way to prepare a variety of tert-butyl carboxylates and highlights the synthetic utility of di- tert-butyl dicarbonate as a versatile carboxylating reagent.

A Route to 1,4-Disubstituted Aromatics and Its Application to the Synthesis of the Antibiotic Culpin

A method is described for converting tert-butyl benzoates or tert-butyl 1-naphthoates into derivatives having an alkyl or substituted alkyl group in a 1,4-relationship to an alkyl, aryl, alkenyl, or alkynyl group. Key steps in the sequence are (i) addition of an organometallic species to a cross-conjugated cyclohexadienone obtained by Birch alkylation of a tert-butyl benzoate or a tert-butyl 1-naphthoate, followed by allylic oxidation, and (ii) treatment with BiCl3 x H2O, which results in removal of the tert-butyl group and spontaneous decarboxylative aromatization. The method was applied to the synthesis of the antimicrobial fungal metabolite culpin.

Síntese do isobutileno e seu emprego em reações de esterificação: propostas de aulas práticas de química orgânica para a graduação

An experiment for the synthesis of isobutylene from tert-butanol dehydratation using oxalic acid as catalyst, followed by preparations of tert-butyl benzoate and tert-butyl cinnamate is described. The synthesis are simple, requiring two periods of 4 hours and are suitable for undergraduate organic chemistry experimental courses.

Chemisorption and Cleavage of Alkyl Benzoates on Alumina Surface Studied by Inelastic Electron Tunneling Spectroscopy

The technique of inelastic electron tunneling spectra (IETS) has been used to study the surface reaction of ethyl, isobutyl, and tert-butyl benzoates on alumina. The ethyl and isobutyl benzoates decompose to the corresponding alcohols where the net reaction accounts for the hydrolysis of the benzoate, and the ultimate products of chemisorption on alumina surface are detected to be the corresponding alkoxide anions. In the case of tert-butyl benzoate, the chemisorbed species on the alumina surface is benzoic acid rather than tert-butyl alcohol. In both cases, the surface reactions are identified as the dissociative chemisorption of the hydrolysis products of the original benzoate molecule

Chemisorbed Species of Alkyl Benzoates on Alumina Surface Studied by Inelastic Electron Tunneling Spectroscopy

Abstract Vibrational spectra of alkyl benzoates dissociatively adsorbed on the alumina surfaces have been measured by inelastic electron tunneling spectroscopy. The analyses of the spectra indicate that ethyl and tert-butyl benzoates are adsorbed as ethoxide or benzoate ions, respectively, by the acid-catalyzed reaction on alumina surfaces.

ChemInform Abstract: NATURE OF THE TRANSITION STATE IN ESTER PYROLYSIS. III. HAMMETT CORRELATION FOR PYROLYSIS OF TERT‐BUTYL BENZOATES

Chemischer InformationsdienstVolume 7, Issue 10 Preparative Organic Chemistry ChemInform Abstract: NATURE OF THE TRANSITION STATE IN ESTER PYROLYSIS. III. HAMMETT CORRELATION FOR PYROLYSIS OF TERT-BUTYL BENZOATES HASSAN B. AMIN, HASSAN B. AMINSearch for more papers by this authorROGER TAYLOR, ROGER TAYLORSearch for more papers by this author HASSAN B. AMIN, HASSAN B. AMINSearch for more papers by this authorROGER TAYLOR, ROGER TAYLORSearch for more papers by this author First published: March 9, 1976 https://doi.org/10.1002/chin.197610078AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume7, Issue10March 9, 1976 RelatedInformation