97479-87-3Relevant academic research and scientific papers
Ni-Catalyzed C(sp3)–O Arylation of α-Hydroxy Esters
Monteith, John J.,Rousseaux, Sophie A. L.
, p. 9485 - 9489 (2021/12/09)
A Negishi cross-coupling of α-hydroxy ester derivatives and arylzinc reagents has been developed. This reaction tolerates both primary and secondary C(sp3)–O alcohol precursors and achieves efficient cross-coupling under Ni catalysis without the need for added external metal reductant, photocatalyst, or additives. The arylation of readily accessible C(sp3)–O electrophiles in this operationally simple, rapid, and mild reaction provides a complementary way of accessing desirable α-aryl ester products.
Electrochemically Enabled, Nickel-Catalyzed Dehydroxylative Cross-Coupling of Alcohols with Aryl Halides
Li, Zijian,Sun, Wenxuan,Wang, Xianxu,Li, Luyang,Zhang, Yong,Li, Chao
supporting information, p. 3536 - 3543 (2021/03/08)
As alcohols are ubiquitous throughout chemical science, this functional group represents a highly attractive starting material for forging new C-C bonds. Here, we demonstrate that the combination of anodic preparation of the alkoxy triphenylphosphonium ion and nickel-catalyzed cathodic reductive cross-coupling provides an efficient method to construct C(sp2)-C(sp3) bonds, in which free alcohols and aryl bromides - both readily available chemicals - can be directly used as coupling partners. This nickel-catalyzed paired electrolysis reaction features a broad substrate scope bearing a wide gamut of functionalities, which was illustrated by the late-stage arylation of several structurally complex natural products and pharmaceuticals.
Palladium-Catalyzed Asymmetric Markovnikov Hydroxycarbonylation and Hydroalkoxycarbonylation of Vinyl Arenes: Synthesis of 2-Arylpropanoic Acids
Guan, Zheng-Hui,Ren, Zhi-Hui,Wang, Yuan,Yang, Hui-Yi,Yao, Ya-Hong,Zou, Xian-Jin
supporting information, p. 23117 - 23122 (2021/09/18)
Asymmetric hydroxycarbonylation is one of the most fundamental yet challenging methods for the synthesis of carboxylic acids. Herein, we reported the development of a palladium-catalyzed highly enantioselective Markovnikov hydroxycarbonylation of vinyl arenes with CO and water. A monodentate phosphoramidite ligand L6 plays vital role in the reaction. The reaction tolerates a range of functional groups, and provides a facile and atom-economical approach to an array of 2-arylpropanoic acids including several commonly used non-steroidal anti-inflammatory drugs. The catalytic system has also enabled an asymmetric Markovnikov hydroalkoxycarbonylation of vinyl arenes with alcohols to afford 2-arylpropanates. Mechanistic investigations suggested that the hydropalladation is irreversible and is the regio- and enantiodetermining step, while hydrolysis/alcoholysis is probably the rate-limiting step.
Pd-Catalyzed Regioselective Hydroesterification of Olefins with 2,2,2-Trifluoroethyl Formate
Chen, Jinhua,Chu, Jianxiao,Huang, Minyan,Ren, Wenlong,Shi, Yian
supporting information, (2020/03/04)
A Pd-catalyzed regioselective hydroesterification of olefins with 2,2,2-trifluoroethyl formate (TFEF) is described. Either linear or branched esters can be selectively obtained with proper ligands in most cases. The reaction process is operationally simple and involves no toxic CO gas.
Stereodivergent Protein Engineering of a Lipase to Access All Possible Stereoisomers of Chiral Esters with Two Stereocenters
Xu, Jian,Cen, Yixin,Singh, Warispreet,Fan, Jiajie,Wu, Lian,Lin, Xianfu,Zhou, Jiahai,Huang, Meilan,Reetz, Manfred T.,Wu, Qi
supporting information, p. 7934 - 7945 (2019/05/22)
Enzymatic stereodivergent synthesis to access all possible product stereoisomers bearing multiple stereocenters is relatively undeveloped, although enzymes are being increasingly used in both academic and industrial areas. When two stereocenters and thus four stereoisomeric products are involved, obtaining stereodivergent enzyme mutants for individually accessing all four stereoisomers would be ideal. Although significant success has been achieved in directed evolution of enzymes in general, stereodivergent engineering of one enzyme into four highly stereocomplementary variants for obtaining the full complement of stereoisomers bearing multiple stereocenters remains a challenge. Using Candida antarctica lipase B (CALB) as a model, we report the protein engineering of this enzyme into four highly stereocomplementary variants needed for obtaining all four stereoisomers in transesterification reactions between racemic acids and racemic alcohols in organic solvents. By generating and screening less than 25 variants of each isomer, we achieved >90% selectivity for all of the four possible stereoisomers in the model reaction. This difficult feat was accomplished by developing a strategy dubbed "focused rational iterative site-specific mutagenesis" (FRISM) at sites lining the enzyme's binding pocket. The accumulation of single mutations by iterative site-specific mutagenesis using a restricted set of rationally chosen amino acids allows the formation of ultrasmall mutant libraries requiring minimal screening for stereoselectivity. The crystal structure of all stereodivergent CALB variants, flanked by MD simulations, uncovered the source of selectivity.
Mechanistic Study of Palladium-Catalyzed Hydroesterificative Copolymerization of Vinyl Benzyl Alcohol and CO
Yee, Gereon M.,Wang, Tong,Hillmyer, Marc A.,Tonks, Ian A.
, p. 1778 - 1786 (2019/04/30)
The copolymerization of vinyl benzyl alcohol (VBA) and carbon monoxide (CO) to give a new polyester poly(VBA-CO) has been achieved via palladium-catalyzed hydroesterification. Reaction conditions involve moderate temperatures, moderate to low CO pressures, and low catalyst loadings to give a low molar mass (Mn 3-4 kg/mol) polymer as a 2:1 mixture of linear to branched repeat units. The polymer molar mass increase is consistent with a step-growth polymerization mechanism, and ester yields of >97% are achieved within 24 h. However, increases in Mn cease beyond 16 h. Control experiments indicate that the degree of polymerization is limited due to a combination of side reactions such as alcoholic end-group oxidation, hydroxycarbonylation, and alcohol acetylation, which lead to the degradation of monomeric and polymeric end groups. When a less promiscuous substrate is used such as 10-undecenol, higher molar masses (Mn 16 kg/mol) are achieved. This method has the potential to be a mild route to new polyester architectures with appropriate mitigation of side reactions.
RhI-Catalyzed Stille-Type Coupling of Diazoesters with Aryl Trimethylstannanes
Liu, Zhen,Xia, Ying,Feng, Sheng,Wang, Shuai,Qiu, Di,Zhang, Yan,Wang, Jianbo
, p. 1379 - 1384 (2015/09/15)
A RhI-catalyzed cross-coupling of diazoester with arylstannane was developed. This reaction represents the first Stille-type coupling that uses a diazo compound as the coupling partner. The reaction is operationally simple and can be carried out under mild conditions, thus providing an alternative approach for the synthesis of α-aryl esters. RhI-carbene migratory insertion process is suggested to be involved as the key step in this Stille-type coupling.
A recyclable CO surrogate in regioselective alkoxycarbonylation of alkenes: Indirect use of carbon dioxide
Gehrtz,Hirschbeck,Fleischer
supporting information, p. 12574 - 12577 (2015/08/06)
Herein, we report a Pd-catalysed alkoxycarbonylation of alkenes based on the use of a recyclable CO2 reduction product, the crystalline and air-stable N-formylsaccharin, as a CO surrogate. The carbonylation proceeds under ambient conditions in an exceptionally complementary regioselective fashion yielding the desired branched products from styrene derivatives and valuable linear esters from alkyl-substituted alkenes.
Imidazole derivatives as accelerators for ruthenium-catalyzed hydroesterification and hydrocarbamoylation of alkenes: Extensive ligand screening and mechanistic study
Konishi, Hideyuki,Muto, Takashi,Ueda, Tsuyoshi,Yamada, Yayoi,Yamaguchi, Miyuki,Manabe, Kei
, p. 836 - 845 (2015/03/14)
Imidazole derivatives are effective ligands for promoting the [Ru3(CO)12]-catalyzed hydroesterification of alkenes using formates. Extensive ligand screening was performed to identify 2-hydroxymethylated imidazole as the optimal ligand. Neither carbon monoxide gas nor a directing group was required, and the reaction also showed a wide substrate generality. The Ru-imidazole catalyst system also promoted intramolecular hydrocarbamoylation to afford lactams. A Ru-imidazole complex was unambiguously analyzed by X-ray crystallography, and it had a trinuclear structure derived from one [Ru3(CO)12] and two ligands. This complex was also successfully used for hydroesterification. The mechanism was examined in detail by using D- and 13C-labeled formates, indicating that the hydroesterification reaction proceeds by a decarbonylation-recarbonylation pathway. Effective imidazole assistant: [Ru3(CO)12]-catalyzed hydroesterification of alkenes by using formates is drastically accelerated by imidazole derivatives and exhibits a broad substrate scope for both alkenes and formates. The Ru-imidazole complex also catalyzes the intramolecular hydrocarbamoylation of alkenes.
Rh(I)-catalyzed cross-coupling of α-diazoesters with arylsiloxanes
Xia, Ying,Liu, Zhen,Feng, Sheng,Ye, Fei,Zhang, Yan,Wang, Jianbo
supporting information, p. 956 - 959 (2015/03/30)
An Rh(I)-catalyzed cross-coupling of diazoesters with arylsiloxanes has been successfully achieved. This transformation is a new method for the construction of the C(sp3)-C(sp2) bond, thus providing an alternative synthesis of α-aryl esters. Rh(I)-carbene migratory insertion has been proposed to be involved in this coupling reaction. The reaction represents the first example of utilizing arylsiloxane as the coupling partner in the carbene-involved cross-coupling reactions.
