38418-15-4Relevant articles and documents
Hydrogen-bond-assisted transition-metal-free catalytic transformation of amides to esters
Huang, Changyu,Li, Jinpeng,Wang, Jiaquan,Zheng, Qingshu,Li, Zhenhua,Tu, Tao
, p. 66 - 71 (2020/11/18)
The amide C-N cleavage has drawn a broad interest in synthetic chemistry, biological process and pharmaceutical industry. Transition-metal, luxury ligand or excess base were always vital to the transformation. Here, we developed a transition-metal-free hydrogen-bond-assisted esterification of amides with only catalytic amount of base. The proposed crucial role of hydrogen bonding for assisting esterification was supported by control experiments, density functional theory (DFT) calculations and kinetic studies. Besides broad substrate scopes and excellent functional groups tolerance, this base-catalyzed protocol complements the conventional transition-metal-catalyzed esterification of amides and provides a new pathway to catalytic cleavage of amide C-N bonds for organic synthesis and pharmaceutical industry. [Figure not available: see fulltext.]
Bu 4 NI-Catalyzed C-C Bond Cleavage and Oxidative Esteri??cation of Allyl Alcohols with Toluene Derivatives
Chen, Yaoyao,Cui, Yongmei,Jia, Xueshun,Li, Chengliang,Li, Jian,Sun, Mingming
, p. 3667 - 3674 (2019/09/30)
A novel oxidative esterification of 1-arylprop-2-en-1-ols with toluene derivatives catalyzed by tetrabutylammonium iodide (TBAI) is reported. The optimization of the reaction conditions illustrates that each of experiment parameters including the catalyst, solvent, and oxidant is significant for present oxidative functionalization. This metal-free protocol has a broad substrate scope including the halogen groups for further functionalization and enriches the reactivity profile of allyl alcohol and toluene derivatives. In addition, this protocol represents a new transformation of allyl alcohol involving C-C bond cleavage and C-O bond forming.
Type 2 Ring-Opening Reactions of Cyclopropanated 7-Oxabenzonorbornadienes with Carboxylic Acid Nucleophiles
Carlson, Emily,Hong, Daniel,Tam, William
, p. 4253 - 4259 (2016/11/26)
Ring-opening reactions of strained heterocyclic compounds provide efficient routes to various organic frameworks. In this work, the ability of carboxylic acid nucleophiles to promote ring-opening of cyclopropanated 7-oxabenzonorbornadienes was investigated. Reactions proceeded smoothly to yield 2-naphthylmethyl esters in moderate yields, and optimal conditions were found with the use of 10 mol% p-toluenesulfonic acid monohydrate in dichloroethane heated to 90 °C. The amount of nucleophile could be decreased from a large excess to 8 equivalents without diminishing the yield. When varying the structure of the acid catalyst or carboxylic acid nucleophile, reaction rates showed a marked dependence on acidity of these species. Ring-opening was well tolerated by functionalized substrates, with substitution on the bridgehead or aromatic portions of the molecule. The present work is the second account of this type of reaction, and provides a new route to 2-naphthylmethyl esters. The transformations observed in this work should be useful in predicting the reactivity of similar fused-ring systems.
