149849-34-3Relevant academic research and scientific papers
Strain-Driven Dyotropic Rearrangement: A Unified Ring-Expansion Approach to α-Methylene-γ-butyrolactones
Lei, Xiaoqiang,Li, Yuanhe,Lai, Yang,Hu, Shengkun,Qi, Chen,Wang, Gelin,Tang, Yefeng
supporting information, p. 4221 - 4230 (2020/12/22)
An unprecedented strain-driven dyotropic rearrangement of α-methylene-β-lactones has been realized, which enables the efficient access of a wide range of α-methylene-γ-butyrolactones displaying remarkable structural diversity. Several appealing features of the reaction, including excellent efficiency, high stereospecificity, predictable chemoselectivity and broad substrate scope, render it a powerful tool for the synthesis of MBL-containing molecules of either natural or synthetic origin. Both experimental and computational evidences suggest that the new variant of dyotropic rearrangements proceed in a dualistic pattern: while an asynchronous concerted mechanism most likely accounts for the reactions featuring hydrogen migration, a stepwise process involving a phenonium ion intermediate is favored in the cases of aryl migration. The great synthetic potential of the title reaction is exemplified by its application to the efficient construction of several natural products and relevant scaffolds.
2 H-Chromene-3-carboxylic Acid Synthesis via Solvent-Controlled and Rhodium(III)-Catalyzed Redox-Neutral C-H Activation/[3 + 3] Annulation Cascade
Zhou, Zhi,Bian, Mengyao,Zhao, Lixin,Gao, Hui,Huang, Junjun,Liu, Xiawen,Yu, Xiyong,Li, Xingwei,Yi, Wei
supporting information, p. 3892 - 3896 (2018/07/22)
An efficient and redox-neutral synthesis of 2H-chromene-3-carboxylic acids from N-phenoxyacetamides and methyleneoxetanones has been realized via a solvent-controlled and rhodium(III)-catalyzed C-H activation/unusual [3 + 3] annulation sequence. This tran
Pd-Catalyzed Acyl C-O Bond Activation for Selective Ring-Opening of α-Methylene-β-lactones with Amines
Malapit, Christian A.,Caldwell, Donald R.,Sassu, Nicole,Milbin, Samuel,Howell, Amy R.
supporting information, p. 1966 - 1969 (2017/04/28)
A Pd-catalyzed ring-opening of β-lactones with various types of amines (primary, secondary, and aryl) to provide β-hydroxy amides with excellent selectivity toward acyl C-O bond cleavage is reported. The utility of this protocol is demonstrated in an asym
Cascade synthesis of spirooxindole δ-lactone derivatives through N-aryl hydroxymethylacrylamides with xanthates
Wang, Shucheng,Huang, Xuhu,Wen, Yanzhao,Ge, Zemei,Wang, Xin,Li, Runtao
supporting information, p. 8117 - 8122 (2015/12/30)
A novel and highly efficient cascade synthesis of spirooxindole δ-lactone derivatives from N-aryl hydroxymethylacrylamides and xanthates in good yields is described. The reaction proceeds through a radical addition/cyclization and ester exchange, in which two new C-C bonds and one C-O bond were formed.
Dibromomethane as one-carbon source in organic synthesis: A versatile methodology to prepare the cyclic and acyclic α-methylene or α-keto acid derivatives from the corresponding terminal alkenes
Hon, Yung-Son,Liu, Yu-Wei,Hsieh, Cheng-Han
, p. 4837 - 4860 (2007/10/03)
Ozonolysis of mono-substituted alkenes A-1 followed by reacting with a preheated mixture of CH2Br2-Et2NH affords α-substituted acroleins A-2 in good yields. Under very mild reaction conditions, these α-substituted acroleins A-2 can be easily converted to α-methylene esters A-4, which could be further converted to the corresponding α-keto esters A-5. This methodology can be also applied to the preparation of α-methylene lactones B-4, α-methylene lactams, and α-keto lactones B-5 with various ring sizes.
