Tandem Wittig Reaction–Ring Contraction of Cyclobutanes: A Route to Functionalized Cyclopropanecarbaldehydes
作者:Federico Cuccu、Lorenzo Serusi、Alberto Luridiana、Francesco Secci、Pierluigi Caboni、David J. Aitken、Angelo Frongia
DOI:10.1021/acs.orglett.9b02690
日期:2019.10.4
An original tandem reaction consisting of a Wittig reaction-ring contraction process between α-hydroxycyclobutanone and phosphonium ylides has been developed. Highly functionalized cyclopropanecarbaldehydes are obtained in good to high yield.
The scope of the novel ruthenium‐catalyzed tandem cross‐metathesis/intramolecular‐hydroarylation sequence is described. This methodology offers a practical and efficient synthesis of structurally diverse and complex tetrahydrocarbazoles in good to excellent yields (up to 98 %). Moreover, preliminary efforts towards the development of an enantioselective version of the current process by sequential
The first enantioselective sequential phosphine-catalyzed (SPC as abbreviation) mode for the formation of tetrahydroquinolines with an ethynyl-substituted all-carbon quaternary stereogenic center is reported. In this SPC process, a novel [4 + 2] annulation process was devised employing α-substituted allenoates as C2 synthons (α–β′, 1,2-dipole) for the first time. 3-Ethynyl-substituted tetrahydroquinolines
Phosphine-Mediated Sequential [2+4]/[2+3] Annulation to Construct Pyrroloquinolines
作者:Junhui Lin、Yannan Zhu、Wei Cai、You Huang
DOI:10.1021/acs.orglett.1c04388
日期:2022.3.4
A domino [2+4]/[2+3] sequentialannulation reaction of MBH carbonates with N-unprotected indoles has been developed to provide various pyrroloquinoline derivatives in ≤94% yield and 20:1 dr. The reaction could be either mediated by stoichiometric PCy3 or catalyzed by R3PO via PIII/PV═O redox cycling in the presence of phenylsilane. This method assembles polycyclic 1,7-fused indoles in one step diastereoselectively
MBH 碳酸盐与 N-未保护的吲哚的多米诺 [2+4]/[2+3] 顺序环化反应已被开发,以提供≤94% 产率和 20:1 dr 的各种吡咯并喹啉衍生物。该反应可以由化学计量的 PCy 3介导,也可以由 R 3 PO 在苯基硅烷存在下通过 P III /P V = O 氧化还原循环催化。该方法一步非对映选择性地组装多环 1,7-稠合吲哚。
Enantioselective Copper(I)-Catalyzed Borylative Aldol Cyclizations of Enone Diones
作者:Alan R. Burns、Jorge Solana González、Hon Wai Lam
DOI:10.1002/anie.201205899
日期:2012.10.22
Piña colato? In the presence of a chiral CuI/bisphosphine complex and B2(pin)2, enone diones undergo diastereo‐ and enantioselective desymmetrization to deliver highly functionalized bicyclic products. The products can be used as substrates in additional transformations. pin=pinacolato, Cy=cyclohexyl.
Piñacolato?在存在手性Cu I /双膦配合物和B 2(pin)2的情况下,烯酮二酮会经历非对映异构和对映选择性去对称化,从而提供高度官能化的双环产物。该产品可用作其他转化的底物。销=松果醇,Cy =环己基。