102970-80-9

Upstream product

• 105-13-5 4-Methoxybenzyl alcohol 
• 637-44-5 phenylpropyolic acid 
• 100867-01-4 (4-methoxybenzyl)(4-nitrophenyl)sulfane 
• 89238-99-3 O-(4-methoxybenzyl)-trichloroacetimidate 
• 124-38-9 carbon dioxide 
• 536-74-3 phenylacetylene 
• 824-94-2 p-methoxybenzyl chloride 

Downstream Products

• 167688-16-6 1-methoxy-4-(3-phenylprop-2-yn-1-yl)benzene 

Relevant academic research and scientific papers

Discriminating non-ylidic carbon-sulfur bond cleavages of sulfonium ylides for alkylation and arylation reactions

A sulfonium ylide participated alkylation and arylation under transition-metal free conditions is described. The disparate reaction pattern allowed the separate activation of non-ylidic S-alkyl and S-aryl bond. Under acidic conditions, sulfonium ylides serve as alkyl cation precursors which facilitate the alkylations. While under alkaline conditions, cleavage of non-ylidic S-aryl bond produces O-arylated compounds efficiently. The robustness of the protocols were established by the excellent compatibility of wide variety of substrates including carbohydrates.

Unprecedented Multicomponent Organocatalytic Synthesis of Propargylic Esters via CO2 Activation

An efficient and straightforward organocatalytic method for the direct, multicomponent carboxylation of terminal alkynes with CO2 and organochlorides, towards propargylic esters, is reported for the first time. 1,3-Di-tert-butyl-1H-imidazol-3-ium chloride, a simple, widely-available, stable, and cost-efficient N-heterocyclic carbene (NHC) precursor salt was used as the (pre)catalyst. A wide range of phenylacetylenes, bearing electron-withdrawing or electron-donating substituents, react with allyl-chlorides, benzyl chlorides, or 2-chloroacetates, providing the corresponding propargylic esters in low to excellent yields. DFT calculations on the mechanism of this transformation indicate that the reaction is initiated with the formation of an NHC-carboxylate, by addition of the carbene to a molecule of CO2. Then, the nucleophilic addition of this species to the corresponding chlorides has been computed to be the rate limiting step of the process.

Silver-catalyzed one-pot synthesis of benzyl 2-alkynoates under ambient pressure of CO2and ligand-free conditions

The carboxylative coupling of aryl/alkyl terminal alkynes, CO2and benzyl halides was investigated using silver iodide as the catalyst and Cs2CO3as the base in CH3CN under ligand-free conditions. This reaction protocol shows a wide substrate scope and high functional group tolerance ability for benzyl halides, in which various functionalized benzyl 2-alkynoates were achieved in good yields. This one-pot, ligand-free and CH3CN mediated reaction proved to be easy to handle and could be facilitated under atmospheric CO2pressure.

Effective Synthesis of Benzyl 3-Phenylpropiolates Via Copper(I)-Catalyzed Esterification of Alkynoic Acids with Benzyl Halides under Ligand-Free Conditions

We developed an efficient way to prepare benzyl 3-phenylpropiolates via copper-catalyzed coupling between corresponding benzyl halides and alkynoic acids under ligand-free condition. This methodology is also suitable for aromatic and α,β-unsaturated acids. The desired esters could be obtained in good yields.

Spontaneous formation of PMB esters using 4-methoxybenzyl-2,2,2- trichloroacetimidate

Carboxylic acids are converted to the corresponding 4-methoxybenzyl (PMB) esters with 4-methoxybenzyl-2,2,2-trichloroacetimidate in the absence of an acid catalyst. This operationally simple procedure is a highly effective method for the formation of PMB esters. The reaction is promoted by the carboxylic acids themselves in excellent yields (72-99%). Sterically hindered carboxylic acids, which provide lower yields with other imidates, are esterified in higher yield with the more reactive PMB imidate. No racemization is observed in the case of carboxylic acids bearing an α-stereocenter, and no isomerization is observed with Z-α,β-unsaturated acids. This method may therefore find use in the esterification of complex or sensitive substrates where more common techniques lead to decomposition.

Ligand-free Ag(I)-catalyzed carboxylative coupling of terminal alkynes, chloride compounds, and CO2

Simple silver(I) slats were found to be highly efficient and selective catalyst for carboxylative coupling of aryl- or alkyl-substituted terminal alkynes, CO2, and various allylic, propargylic or benzylic chlorides to exclusively yield function

Decarboxylative benzylations of alkynes and ketones

Benzyl esters of propiolic and β-keto acids undergo catalytic decarboxylative coupling when treated with appropriate palladium catalysts. Such decarboxylative couplings allow the benzylation of alkynes without the use of strong bases and/or organometallics. This allows the synthesis of sensitive benzylic alkynes that are prone to undergo isomerizations under basic conditions. Additionally, decarboxylation facilitates the site-specific benzylation of diketones and ketoesters under mild, base-free conditions. Ultimately, the methodology described expands our ability to cross-couple medicinally relevant heterocycles.