Combination of Metal-Catalyzed Cycloisomerizations and Biocatalysis in Aqueous Media: Asymmetric Construction of Chiral Alcohols, Lactones, and γ-Hydroxy-Carbonyl Compounds
作者:María J. Rodríguez-Álvarez、Nicolás Ríos-Lombardía、Sören Schumacher、David Pérez-Iglesias、Francisco Morís、Victorio Cadierno、Joaquín García-Álvarez、Javier González-Sabín
DOI:10.1021/acscatal.7b02183
日期:2017.11.3
The combination of the metal-catalyzed cycloisomerization of alkynes containing a tethered nucleophile as substituent in aqueousmedia (followed by the spontaneous hydrolysis, hydroalkoxylation, or aminolysis of the transiently formed five-membered heterocycles) with the subsequent enantioselective ketone bioreduction (mediated by KREDs) has been achieved. The overall transformations, which formally
A Phosphine-Free Manganese Catalyst Enables Stereoselective Synthesis of (1 + <i>n</i>)-Membered Cycloalkanes from Methyl Ketones and 1,<i>n</i>-Diols
作者:Akash Jana、Kuhali Das、Abhishek Kundu、Pradip Ramdas Thorve、Debashis Adhikari、Biplab Maji
DOI:10.1021/acscatal.9b05567
日期:2020.2.21
Herein, we report the stereoselective synthesis of (1 + n)-membered cycloalkane from methyl ketone and 1,n-diol. A manganese(I) complex bearing a phosphine-free ligand catalyzed the reaction, which involved the formation of two C–C bonds via a sequence of intermolecular- and intramolecular-borrowing hydrogenation reactions. It produces 2 mol of water as the sole byproduct, making the process atom economical
A copper-promoted flexible synthesis of cyclobutenes carrying simple alkyl chains, enabling even the most hindered nucleophiles to be employed, has been developed. The versatility of this approach was exemplified by a short total synthesis of ieodomycin D and a straightforward preparation of the southeastern fragment of macrolactin A. The latter features a late-stage, double cyclobutene electrocyclic
已经开发出一种由铜促进的带有简单烷基链的环丁烯的灵活合成,即使是最受阻的亲核试剂也能被使用。这种方法的多功能性体现在碘霉素 D 的短全合成和大环乳素 A 东南片段的直接制备。后者具有后期双环丁烯电环开环,可直接提供定义几何形状的双二烯.
Sulfonamide compounds and uses thereof
申请人:Smith David W.
公开号:US06967196B1
公开(公告)日:2005-11-22
In accordance with the present invention, there is provided a novel class of sulfonamide compounds. Compounds of the invention contain a core sulfonamide group. Variable moieties connected to the sulfur atom and nitrogen atom of the sulfonamide group include substituted or unsubstituted hydrocarbyl moieties, substituted or unsubstituted heterocycle moieties, polycyclic moieties, halogen, alkoxy, ether, ester, amide, sulfonyl, sulfonamidyl, sulfide, carbamate, and the like. Invention compounds are capable of a wide variety of uses. For example sulfonamide compounds can act to modulate production of amyloid β protein and are useful in the prevention or treatment of a variety of diseases. Pharmaceutical compositions containing invention compounds are also provided. Such compositions have wide utility for the prevention or treatment of a variety of diseases.
Asymmetric hydrosilylation of simple terminal alkenes (RCH=CH2) with trichlorosilane at 40 °C in the presence of 1 × 10−3 or 1 × 10−4 molar amounts of palladium catalyst prepared in situ from [PdCl(η3-C3H5)]2 and (S)-2-diphenylphosphino-2′-methoxy-1,1′-binaphthyl ((S)-MeO-MOP) proceeded with unusual regioselectivity and with high enantioselectivity to give high yields of 2-(trichlorosilyl)alkanes together
在由 [PdCl(η3-C3H5)]2 原位制备的 1 × 10−3 或 1 × 10−4 摩尔量的钯催化剂存在下,简单末端烯烃 (RCH=CH2) 与三氯硅烷在 40 °C 的不对称氢化硅烷化(S)-2-二苯基膦基-2'-甲氧基-1,1'-联萘 ((S)-MeO-MOP) 以不寻常的区域选择性和高对映选择性进行,得到高产率的 2-(三氯甲硅烷基)烷烃少量的 1-(三氯甲硅烷基)烷烃。通过碳-硅键的氧化获得旋光醇,RCH(OH)CH3。相对于 1-甲硅烷基烷烃形成 2- 甲硅烷基烷烃的区域选择性和醇的对映体纯度如下:R = n-C4H9:89/11,94% ee (R)。R = n-C6H13:93/7 95% ee (R)。R = n-C10H21:94/6,95% ee (R)。R = Ph :81/19,97% ee (S)。R = Ph :80/20,92%