935254-77-6Relevant articles and documents
PPh3-catalyzed β-selective addition of α-fluoro β-dicarbonyl compounds to allenoates
Liu, Yong-Liang,Wang, Xiao-Ping,Wei, Jie,Li, Ya
supporting information, (2021/12/02)
A highly selective phosphine-catalyzed β-addition of α-fluoro β-dicarbonyl compounds to allenoates has been developed. Both α-fluoro β-diketones and α-fluoro β-keto esters prove to be competent fluorocarbon nucleophiles, giving a series of the β-addition products bearing a fluorinated quaternary carbon center in good to excellent yields and with excellent regioselectivities. A plausible reaction pathway is presented.
Unified approach to substituted allenoates via Pd-catalyzed β-hydride elimination of (E)-enol triflates
El Arba, Marie,Dibrell, Sara E.,Crouch, Ian T.,Frantz, Doug E.
supporting information, p. 5446 - 5449 (2017/11/06)
A robust synthesis of allenoates via a Pdcatalyzed β-hydride elimination of (E)-enol triflates is presented. Salient features of this method include low catalyst loadings, mild reaction conditions, and the ability to access all four patterns of substituted allenoates from a single substrate class.
Bifunctional-Phosphine-Catalyzed Sequential Annulations of Allenoates and Ketimines: Construction of Functionalized Poly-heterocycle Rings
Li, Erqing,Jin, Hongxing,Jia, Penghao,Dong, Xuelin,Huang, You
supporting information, p. 11591 - 11594 (2016/10/24)
A highly stereoselective sequential annulation reaction between γ-substituted allenoates and ketimines was reported. By using bifunctional N-acyl aminophosphine catalysts, poly-heterocycle rings were obtained with high stereocontrol in good to excellent yields. The desired products have four contiguous stereogenic centers (one quaternary and three tertiary carbon centers), and only one isomer was obtained in all reactions.
Phosphine-catalyzed domino reaction: A novel sequential [2+3] and [3+2] annulation reaction of γ-substituent allenoates to construct bicyclic[3, 3, 0]octene derivatives
Li, Erqing,Huang, You
supporting information, p. 948 - 950 (2014/01/06)
We have successfully developed a novel and efficient phosphine-catalyzed sequential [2+3] and [3+2] annulation reaction of γ-substituent allenoates to construct bicyclic[3, 3, 0]octene derivatives. The protocol uses readily available γ-substituent allenoa
Phosphine-catalyzed domino reactions: A route to functionalized bicyclic skeletons
Li, Erqing,Huang, You
supporting information, p. 3520 - 3527 (2014/04/03)
A novel strategy that involves phosphine-catalyzed sequential [2+3] and [3+2] annulation reactions was developed. In this domino reaction, γ-substituted allenoates were used as novel C4 synthons, and the bicyclic cyclopenta[b]dihydrofuran derivatives were produced in good to excellent diastereoselectivities and yields under mild conditions. Furthermore, preliminary studies on an asymmetric variant of this reaction proceeded with moderate enantioselectivity.
Phosphine-catalyzed [4 + 2] annulation of γ-substituent allenoates: Facile access to functionalized spirocyclic skeletons
Li, Erqing,Huang, You,Liang, Ling,Xie, Peizhong
supporting information, p. 3138 - 3141 (2013/07/26)
The first phosphine-catalyzed [4 + 2] annulation of γ-substituted allenoates with 2-arylidene-1H-indene-1,3(2H)-diones is disclosed. In the reaction, the γ-substituted allenoate serves as a new type of 1,4-dipolar synthon; this broadens the application of
Phosphine-mediated olefination between aldehydes and allenes: An efficient synthesis of trisubstituted 1,3-dienes with high E-selectivity
Xu, Silong,Zhou, Lili,Zeng, San,Ma, Renqin,Wang, Zhihong,He, Zhengjie
supporting information; experimental part, p. 3498 - 3501 (2009/12/01)
The phosphine-mediated olefination of aldehydes with electron-deficient allenes to afford trisubstituted conjugated dienes in fair to excellent yields with high E-selectivity is described. The reaction represents a new reactivity pattern of allenes with aldehydes and also provides a highly stereoselective synthetic method for preparing conjugated dienes. In the reaction, the phosphine acts as a nucleophilic promoter to generate in situ an active phosphorus ylide which mediates the intermolecular olefination.
Phosphane-catalyzed [3+2] annulation of allenoates with aldehydes: A simple and efficient synthesis of 2-alkylidenetetrahydrofurans
Xu, Silong,Zhou, Lili,Ma, Renqin,Song, Haibin,He, Zhengjie
supporting information; experimental part, p. 8698 - 8702 (2010/03/25)
A phosphane-catalyzed [3 +2] annulation of γ-methyl allenoates with aromatic aldehydes has been reported. This annulation provides a convergent and efficient synthesis of 2-alkylidenetetrahydrofurans, which are versatile synthetic building blocks for a vast array of 5-membered oxygenated heterocycle derivatives. The EIZ isomers of 2-(ethoxycarbonylmethylene) tetrahydrofurans, was separated by column chromatography on silica gel and their structural assignments were confirmed by H and C NMR spectroscopy data and X-ray crystallographic analysis. The nature of the substituent, as well as the reaction conditions, has a significant influence on the reactivity patterns of γ-substituted allenoates with aldehydes. The phosphorus ylide, generated from the phosphonium dienolate 8 by an overall 1,4-hydrogen shift, is believed to be the key intermediate responsible for the [3 + 2] annulation and other transformations of γ-methyl allenoates with aldehydes.
Allene carboxylates as dipolarophiles in Rh-catalyzed carbonyl ylide cycloadditions
Rout, Laxmidhar,Harned, Andrew M.
supporting information; experimental part, p. 12926 - 12928 (2010/05/19)
Face-to-face: Allene carboxylates can serve as efficient dipolarophiles for Rh-catalyzed carbonyl ylide cycloadditions (see scheme). The endo and exo products arise from cycloaddition on the same face of the allene, but opposite faces of the dipole. This facial selectivity results in the formation of two of the four possible diastereomers.
A straightforward and mild synthesis of functionalized 3-alkynoates
Suarez, Andres,Fu, Gregory C.
, p. 3580 - 3582 (2007/10/03)
Diazoacetates in coupling reactions: CuI serves as an effective catalyst for coupling terminal alkynes with diazo compounds to generate 3-alkynoates (see scheme). This method is efficient (1:1 ratio of reactants), mild (room temperature), and simple (no a
