A novel product‐derived bimetallic palladium complexcatalyzes a sulfonylazide‐transfer reaction with the σ‐donor/π‐acceptor ligand CO, and is advantageous given its broad substrate scope, high efficiency, and mild reaction conditions (atmospheric pressure of CO at room temperature). This methodology provides a new approach to sulfonylureas, which are present in both pharmaceuticals and agrochemicals
Neutral complexes [Rh (dmgH)2 LX](dmgH2= dimethylglyoxime; L = Ph3P, Ph3As, Ph3Sb; X = Cl, Br, I) may be prepared from rhodium(III) halides, dimethylglyoxime and the ligand in aqueousethanol.
中性配合物[Rh(dmgH)2 LX](dmgH 2 =二甲基乙二肟; L = Ph 3 P,Ph 3 As,Ph 3 Sb; X = Cl,Br,I)可由卤化铑(III),二甲基乙二肟和乙醇水溶液中的配体。
Atom-economy Synthesis of<i>N</i>-Substituted Carbamate from Urea Derivative and Dimethyl Carbonate Catalyzed by La/SiO<sub>2</sub>: Characterization and Activity
作者:Xiaoguang Guo、Jianpeng Shang、Jian Li、Liguo Wang、Yubo Ma、Feng Shi、Youquan Deng
DOI:10.1002/cjoc.201090048
日期:2010.2
silica gel immobilized lanthanum catalysts were prepared for the atom‐economy synthesis of N‐substituted carbamatesfromureaderivatives and dimethylcarbonate. The La/SiO2 catalysts with lanthanum loadings varied from 1.3 wt% to 8.5 wt% were characterized by AES, BET, XRD, TEM, FT‐IR, XPS and TPD. According to the characterization, lanthanum species with particle sizes of 5–10 nm on the surface of silica
制备了一系列硅胶固定的镧催化剂,用于从尿素衍生物和碳酸二甲酯的原子经济合成N-取代的氨基甲酸酯。镧负载量为1.3wt%至8.5wt%的La / SiO 2催化剂通过AES,BET,XRD,TEM,FT-IR,XPS和TPD进行表征。根据表征,在硅胶表面上形成了粒径为5-10 nm的镧物种。催化剂均为无定形,表面积为336.5–530.2 m 2 / g。NH 3 -TPD分析表明,所有样品均显示出相似的酸强度和不同的酸量。FT-IR测量表明,催化剂表面的镧成分为La(OH)3,LaOOH和水合La 2 O 3。另外,镧负载量为4.3重量%时,获得了LaOOH的绝对量的峰值。当镧负载量大于4.3重量%时,BET表面积显着降低。考虑到从催化反应获得的结果,可以得出结论,LaOOH是可能的活性物质,并且高表面积对于高催化活性是重要的。
Green and Practical Synthesis of Carbamates from Ureas and Organic Carbonates
作者:Xiaoguang Guo、Jianpeng Shang、Jian Li、Liguo Wang、Yubo Ma、Feng Shi、Youquan Deng
DOI:10.1080/00397911003707055
日期:2011.3.28
Abstract A practical method for the synthesis of carbamatesfromureas and organic carbonates was developed with 100% atom economy using La2O3/SiO2 as catalyst without any additional solvent. The scope of the protocol is demonstrated in the synthesis of 14 carbamates with various functional groups in excellent yields (76–95%).
Topical formulation and method for preventing or treating acne
申请人:Wu Lester J.
公开号:US10548862B2
公开(公告)日:2020-02-04
Provided is a topical formulation for preventing or treating acne, including a benzenesulfonamide derivative, and a pharmaceutically or cosmetically acceptable excipient. Also provided is a method for preventing or treating acne, including applying the topical formulation on skin of a subject in need thereof.