- Production method of methyl p-tert-butylphenylacetate
-
The invention discloses a production method of methyl p-tert-butylphenylacetate. The method takes p-tert-butylphenylacetic acid and absolute methanol as initial raw materials, and comprises the following reaction operations: heating and refluxing for esterifying and dehydrating p-tert-butylphenylacetic acid and absolute methanol as raw materials under the catalytic action of trifluoromethanesulfonic acid, after the reaction is completed, distilling excessive methanol, cooling residues to room temperature, washing an organic phase once by using a saturated saline solution, standing for layering, separating a water phase, combining the organic phases, neutralizing the organic phases by using 10% sodium carbonate liquid until the pH value is 7-8, standing for layering, separating the water phase, desolventizing the organic phases to the bottom temperature of 80 DEG C, cooling to obtain a crude product, carrying out reduced pressure rectification, and collecting fractions at 122-124 DEG C/1.2 Kpa to obtain the finished product of the methyl p-tert-butylphenylacetate. The raw materials are easy to obtain and low in price, conditions are easy to control and operate, and the product is low in cost, good in quality and suitable for large-scale production.
- -
-
Paragraph 0017-0032
(2022/01/08)
-
- B(C6F5)3-catalyzed O-H insertion reactions of diazoalkanes with phosphinic acids
-
A highly efficient base-, metal-, and oxidant-free catalytic O-H insertion reaction of diazoalkanes and phosphinic acids in the presence of B(C6F5)3has been developed. This powerful methodology provides a green approach towards the synthesis of a broad spectrum of α-phosphoryloxy carbonyl compounds with good to excellent yields (up to 99% yield). The protocol features the advantages of operational simplicity, high atom economy, practicality, easy scalability and environmental friendliness.
- Jiang, Jun,Zhang, Xinzhi,Zhang, Yangyang,Zhao, Jincheng
-
supporting information
p. 5772 - 5776
(2021/07/12)
-
- B(C6F5)3-Catalyzed site-selective N1-alkylation of benzotriazoles with diazoalkanes
-
Alkylation of benzotriazoles is synthetically challenging, often leading to mixtures of N1 and N2 alkylation. Herein, metal-free catalytic site-selective N1-alkylation of benzotriazoles with diazoalkanes is described in the presence of 10 mol% of B(C6F5)3. These reactions provide N1-alkylated benzotriazoles in good to excellent yields and this protocol is successfully adapted to gram-scale syntheses as well as a derivative with antimicrobial activity.
- Guo, Jing,Mandal, Dipendu,Stephan, Douglas W.,Wu, Yile,Zhao, Yunbo
-
supporting information
p. 7758 - 7761
(2021/08/13)
-
- Pd-Catalyzed Decarboxylative Olefination: Stereoselective Synthesis of Polysubstituted Butadienes and Macrocyclic P-glycoprotein Inhibitors
-
The efficient and stereoselective synthesis of polysubstituted butadienes, especially the multifunctional butadienes, represents a great challenge in organic synthesis. Herein, we wish to report a distinctive Pd(0) carbene-initiated decarboxylative olefination approach that enables the direct coupling of diazo esters with vinylethylene carbonates (VECs), vinyl oxazolidinones, or vinyl benzoxazinones to afford alcohol-, amine-, or aniline-containing 1,3-dienes in moderate to high yields and with excellent stereoselectivity. This protocol features operational simplicity, mild reaction conditions, a broad substrate scope, and gram-scalability. Notably, a structurally unique allylic Pd(II) intermediate was isolated and characterized. DFT calculation and control experiments demonstrated that a rare Pd(0) carbene intermediate could be involved in this reaction. Moreover, the polysubstituted butadienes as novel building blocks were unprecedentedly assembled into macrocycles, which efficiently inhibited the P-glycoprotein and dramatically reversed multidrug resistance in cancer cells by 190-fold.
- Chen, Xiangyang,Hao, Jiping,Houk, K. N.,Li, Yingzi,Lou, Liguang,Quan, Haitian,Song, Bichao,Wang, Lu,Xia, Yuanzhi,Xie, Peipei,Xu, Zhongliang,Yang, Weibo
-
supporting information
p. 9982 - 9992
(2020/06/27)
-
- Palladium-Catalyzed Carbonylative Direct Transformation of Benzyl Amines under Additive-Free Conditions
-
In this communication, we developed a new procedure for the direct carbonylative transformation of benzyl amines. Using dimethyl carbonate as the solvent, methyl 2-arylacetates can be produced in good to excellent yields from the corresponding primary, secondary, and tertiary benzyl amines with palladium as the catalyst. Notably, no base or any other additive is required here. In addition, our procedure can also be applied in the preparation of methylphenidate, which is a marketing drug and used in the treatment of attention deficit hyperactivity disorder (ADHD) and narcolepsy.
- Li, Yahui,Wang, Zechao,Wu, Xiao-Feng
-
p. 738 - 741
(2018/01/17)
-
- PROCESS FOR PRODUCTION OF THIOPHENE COMPOUND AND INTERMEDIATE THEREOF
-
To provide a novel process for producing a 2-aryl-3-hydroxy-4-substituted carbonyl thiophene compound or an intermediate thereof useful as an intermediate for production of medicines and agricultural chemicals. A 2-aryl acetate compound represented by the formula (1): wherein R1 is an aryl group or the like, R4 is a C1-3 alkyl group or the like, and X is a leaving group, is reacted with a thioacetic acid compound to form a thioacetyl compound (3), the thioacetyl compound (3) is reacted with a vinyl ketone compound to form a γ-ketosulfide compound (5), which is cyclized under basic conditions to form a dihydrothiophene compound (6), and the dihydrothiophene compound (6) is oxidized by using an oxidizing agent to produce a 2-aryl-3-hydroxy-4-substituted carbonyl thiophene compound (7).
- -
-
Page/Page column 10
(2010/11/17)
-
- 1,2-disubstituted-6-oxo-3-phenyl-piperidine-3-carboxamides and combinatorial libraries thereof
-
The invention relates to combinatorial libraries containing two or more novel piperidine-3-carboxamide derivative compounds, methods of preparing the piperidine-3-carboxamide derivative compounds and piperidine-3-carboxamide derivative compounds bound to a resin
- -
-
-
- Non-imidazole histamine H3 ligands. Part I. Synthesis of 2-(1-piperazinyl)- and 2-(hexahydro-1H-1,4-diazepin-1-yl)benzothiazole derivatives as H3-antagonists with H1 blocking activities
-
New 2-(1-Piperazinyl)- and 2-(hexahydro-1H-1,4-diazepin-1-yl)benzothiazoles were prepared and tested as H1- and H3-receptor antagonists. A number of compounds showed weak H1-antagonistic activity, with pA2 values ranging from 5.5 to 6.1. The simple alkyl substituted, 2-[1-(4-methyl and 4-ethyl)piperazinyl] analogues show increasing, moderate H3-antagonistic activity (pA2=6.0, and pA2=7.0). The compounds with 4-phenylalkyl substitution, for both the piperazinyl and the hexahydro-1H-1,4-diazepin-1-yl homologues series, regardless of the different physicochemical properties of the para substituents at the phenyl ring, showed weak H3-antagonistic activity with pA2 values ranging from 4.4 to 5.6. Copyright (C) 1999 Elsevier Science S.A.
- Walczynski, Krzysztof,Guryn, Roman,Zuiderveld, Obbe P.,Timmerman, Henk
-
p. 684 - 694
(2007/10/03)
-