Telescoping Reactions with Trifluorodiazoethane-Derived Aza-Wittig Reagents and Allenyl esters
作者:Fa-Guang Zhang、Jun-Liang Zeng、Yi-Qiang Tian、Yan Zheng、Dominique Cahard、Jun-An Ma
DOI:10.1002/chem.201801171
日期:2018.5.28
developed for the novel functionalization of allenyl esters. First, new phosphazenes derived from trifluorodiazoethane and phosphines were generated and reacted with allenyl esters to give unexpected α‐iminophosphoranes through the creation of C=P, C=N, and C−H bonds at the α‐, β‐, and γ‐carbon atoms, respectively, of the allenyl esters. The α‐iminophosphoranes did not react with aldehydes in a classic Wittig
Regio- and Stereoselective Copper(II)-Catalyzed Hydrosilylation of Activated Allenes in Water: Access to Vinylsilanes
作者:Srinath Pashikanti、Joseph A. Calderone、Matthew K. Nguyen、Christopher D. Sibley、Webster L. Santos
DOI:10.1021/acs.orglett.6b00981
日期:2016.5.20
By using catalytic amounts of copper(II), 4-picoline, and dimethylphenylsilylpinacol borane, a series of allenoates were silylated on the β carbon in good to excellent yields and high (E)-selectivity. The mild and efficient silylation method is conducted in water under atmospheric conditions to afford vinylsilanes.
Phosphine-catalyzed dearomative [3+2] annulation of 3-nitroindoles and allenoates
作者:Kui Liu、Gang Wang、Shao-Jie Cheng、Wen-Feng Jiang、Cheng He、Zhi-Shi Ye
DOI:10.1016/j.tetlet.2019.06.016
日期:2019.7
dearomative [3+2] annulation of 3-nitroindoles with allenoates has been successfully developed, providing a facile access to cyclopenta[b]indolines with good to excellent yields and high diastereoselectivities. This strategy features mild reaction conditions, high functional group tolerance, and scalability. Additionally, the 2-nitrobenzofuran and 2-nitrobenzothiophene were good dearomative [3+2] annulation
已经成功开发了有效的膦催化的3-硝基吲哚与脲基甲酸酯的脱芳族环氧化物[3 + 2]环化反应,可轻松获得环戊二烯[ b ]吲哚,并具有良好或优异的收率和较高的非对映选择性。该策略具有温和的反应条件,较高的官能团耐受性和可扩展性。此外,2-硝基苯并呋喃和2-硝基苯并噻吩是良好的脱芳香性[3 + 2]环空伙伴。
Selective One-Pot Synthesis of Allenyl and Alkynyl Esters from β-Ketoesters
作者:Pradip Maity、Salvatore D. Lepore
DOI:10.1021/jo801563x
日期:2009.1.2
β-ketoesters to generate conjugated and deconjugated alkynyl esters and conjugated allenyl esters. This sequential one-pot method involves the formation of a vinyl triflate monoanion intermediate that leads to the selective formation of alkynes or allenes depending on additives and conditions used. Product outcomes appear to be a function of unique mono- and dianion mechanisms which are described.
Asymmetric Aldol Reaction of Allenoates: Regulation for the Selective Formation of Isomeric Allenyl or Alkynyl Aldol Adduct
作者:Jiyun Bang、Hyuna Kim、Jihyun Kim、Chan-Mo Yu
DOI:10.1021/acs.orglett.5b00454
日期:2015.3.20
A highly stereoselective synthesis of 3-butynyl-threo-aldol adducts is achieved from the reaction of allyl allenoate with a chiral bromoborane in the presence of iPr2NEt, followed by addition of BF3·OEt2 as an additive to scavenge excess base and then aldehydes, whereas isomeric allenyl aldol adducts are formed in the absence of a Lewis acid additive from methyl allenoate.