97699-36-0Relevant academic research and scientific papers
Rhodium-Catalyzed Regioselective Formal Hydroacylation of Vinyl Epoxides toward Esters Involving β-Carbon Cleavage
Chang, Zhi-Xin,Gong, Fei-Yuan,Wang, Xiaodan,Zhang, Tongbo,Han, Junfen,Li, Hong-Shuang
, p. 6084 - 6089 (2021/08/16)
Herein we disclose the first example of the formal hydroacylation reactions of vinyl epoxides with chelating aldehydes enabled by rhodium catalysis for the efficient construction of functionalized esters. Detailed investigations of the mechanistic pathway reveal that the presence of a 2-vinyl group is essential in contributing to the success of this regioselective reaction, which might proceed through β-carbon cleavage as the key procedure.
A synthetic strategy toward eight-membered cyclic amines by cycloetherification and claisen rearrangement
Han, Seo-Jung,Cavitt, Marchello A.,Stoltz, Brian M.
supporting information, p. 3300 - 3303 (2021/05/07)
Eight-membered nitrogen-containing heterocycles were straightforwardly produced by a nickel-catalyzed cycloetherification and subsequent Claisen rearrangement of secondary and tertiary alcohols. In particular, a one-pot transformation was achieved with tertiary alcohols in moderate to good yields. This operationally simple reaction is tolerant of many functional groups and applicable to the synthesis of various medium-sized ring nitrogen-containing heterocycles.
Synthetic Strategy for Tetraphenyl-Substituted All-E-Carotenoids with Improved Molecular Properties
Chung, Wook-Jin,Jung, Hyunuk,Koo, Sangho,Lim, Boram,Park, Myeongnam,Yang, Huijeong,Yoo, Hyebin
, (2020/03/13)
The synthetic method of tetraphenyl-substituted all-E-carotenes 1 with improved properties of antioxidant and molecular electronic conductance was developed through the formation of tetraphenyl-substituted all-E-apocarotenedial 4. The synthesis highlighted the preparation of novel subunits containing phenyl substituent(s) with E-configuration starting from the key (E)-4-chloro-2-phenylbut-2-enal (10), utilizing conjugation effect with formyl group or easy recrystallization of sulfone compounds. Sulfone-mediated coupling methods of Julia and modified Julia–Kocienski olefinations utilizing the subunits were demonstrated to produce tetraphenyl-substituted apocarotenedials 4. The major all-E-forms (73–85 % selectivity) were easily purified by SiO2 chromatography and trituration with Et2O due to the presence of the polar formyl groups. The olefination of all-E-apocarotenedials 4 and Wittig salt 5 provided all-E-9,9',13,13'-tetraphenylcarotenes 1.
2,7-DIPHENYLOCTA-2,4,6-TRIENEDIAL, METHOD FOR PREPARING THE SAME AND METHOD FOR PREPARING CAROTENOIDS CONTAINING PHENYL SUBSTITUENTS USING THE SAME
-
Paragraph 0124-0127, (2019/02/27)
The present invention relates to an intermediate, a method for synthesizing the same, and a method for efficiently synthesizing a carotene compound containing a phenyl substituent using the same, wherein the intermediate needed to prepare a polyene structure of a carotene compound having a variety of physicochemical and electroelectronic properties according to electronic properties of the phenyl substituent in a single step reaction, and exhibiting improved antioxidant abilities by containing the phenyl substituent. To this end, 2,7-diphenyl-2,4,6-trienedial of chemical formula 1, which is a novel compound, and 2-((3-(5,5-dimethyl-1,3-dioxane-2-yl)-3-phenylallyl)sulfonyl)benzo[d]thiazole of chemical formula 2, and a synthesis method thereof are proposed by an efficient method using a common intermediate. The novel compound can be efficiently used for synthesis of a carotene compound containing various phenyl substituents through a Julia-Kocienski reaction or a Wittig reaction.COPYRIGHT KIPO 2019
Palladium-Catalyzed Highly Stereoselective Dearomative [3 + 2] Cycloaddition of Nitrobenzofurans
Cheng, Qiang,Zhang, Hui-Jun,Yue, Wen-Jun,You, Shu-Li
supporting information, p. 428 - 436 (2017/09/22)
Stereoselective construction of highly functionalized heterocyclic molecules is an ongoing concern for the chemical community. Among the various strategies developed with this goal, catalytic asymmetric dearomatization, an attractive method for constucting cyclic molecules with multiple stereocenters from readily available aromatic compounds, has received extensive attention in recent years. Here, we report a highly stereoselective construction of tetrahydrofurobenzofurans and tetrahydrofurobenzothiophenes via palladium-catalyzed dearomative [3 + 2] cycloaddition of nitrobenzofurans and nitrobenzothiophenes, respectively. Good to excellent yields (63%–92%), diastereoselectivity (13/1 → >20/1 dr), and enantioselectivity (75%–95% ee) were obtained, leading to products with vicinal stereogenic carbon centers. The reaction features wide substrate scope and diverse transformations of the products.
Mild stereoselective formation of tri- and tetrasubstituted olefins by regioselective ring opening of 1,1-disubstituted vinyl oxiranes with dialkyl dithiophosphates
Guo, Boying,Vitaku, Edon,Njardarson, Jon T.
supporting information, p. 3232 - 3234 (2014/06/09)
Presented in this Letter is a mild new method to stereoselectively ring open 1,1-disubstituted vinyl oxiranes using dialkyl dithiophosphate nucleophiles. This new reaction proceeds in toluene at room temperature to afford tri- and tetrasubstituted allylic alcohols with high Z-selectivity. The syn relationship between the alcohol and the newly incorporated dithiophosphate moiety presented an opportunity to evaluate the anionic hopping properties of the ring opening product. Treatment of the ring opening product with base results in a facile phosphate hopping followed by a selective thiolate 3-exo-trig instead of a 5-exo-tet cyclization.
