38002-87-8Relevant academic research and scientific papers
tert-Butyl Hydroperoxide-Initiated Radical Cyclization of 1-(Allyloxy)-2-(1-Arylvinyl)Benzenes with Sulfinic Acids to Access Sulfonated Benzoxepines
Kuang, Kaimo,Wu, Meixia,Wu, Sixin,Xia, Ziqin,Xu, Qiankun,Zhang, Man,Zhou, Nengneng
supporting information, p. 3491 - 3495 (2021/06/28)
A tert-butyl hydroperoxide-initiated radical cyclization of 1-(allyloxy)-2-(1-arylvinyl)benzenes with sulfinic acids for the construction of sulfonated benzoxepines is developed. This reaction involves a radical pathway and offers a straightforward route to the formation of seven-membered ring via sulfonylation/cyclization process. This methodology features mild reaction conditions, a broad substrate scope and good functional group tolerance. (Figure presented.).
Cascade Claisen and Meinwald Rearrangement for One-Pot Divergent Synthesis of Benzofurans and 2 H-Chromenes
Song, Liyan,Su, Qian,Lin, Xi,Du, Zhihui,Xu, Huiyou,Ouyang, Ming-An,Yao, Hongliang,Tong, Rongbiao
supporting information, p. 3004 - 3009 (2020/04/20)
A new cascade approach has been developed for the one-pot four-step divergent synthesis of polysubstituted benzofurans and 2H-chromenes, featuring a novel cascade aromatic Claisen rearrangement/Meinwald rearrangement/dehydrative or oxidative cyclization. This new method was demonstrated with 39 examples tolerating different substitutions at an epoxide, allylic ether, and aromatic ring, and we showcased its utility with the first total synthesis of natural product liparacid A in seven steps.
Synthesis of Chromenoisoxazolidines from Substituted Salicylic Nitrones via Visible-Light Photocatalysis
Haun, Graham,Paneque, Alyson N.,Almond, David W.,Austin, Brooke E.,Moura-Letts, Gustavo
supporting information, p. 1388 - 1392 (2019/03/08)
This effort reports the first redox-neutral visible-light photocatalytic intramolecular dipolar cycloaddition for the diastereoselective synthesis of chromenoisoxazolidines. The authors have found that alkenylphenyl nitrones with a diverse substitution pattern on the aromatic ring and the alkenyl substituent undergo visible-light-promoted cycloadditions in the presence of catalytic amounts of Ru(bpy)3Cl2 in high yields and selectivities. Evidence indicates that the proposed redox-neutral pathway is the predominant photoredox mechanism for this transformation.
A cascade Claisen rearrangement/o-quinone methide formation/electrocyclization approach to 2H-chromenes
Song, Liyan,Huang, Fang,Guo, Liwen,Ouyang, Ming-An,Tong, Rongbiao
supporting information, p. 6021 - 6024 (2017/07/10)
A new approach has been developed for the synthesis of 8-substituted 2H-chromenes, featuring a novel cascade aromatic Claisen rearrangement/o-quinone methide formation/6π-electrocyclization. This new method was demonstrated with 28 examples tolerating different substitutions at alkenes, allylic and aromatic ring and with total syntheses of three 2H-chromene natural products.
Silaborative Carbocyclizations of 1,7-Enynes. Diastereoselective Preparation of Chromane Derivatives
Xiao, You-Cai,Moberg, Christina
supporting information, p. 308 - 311 (2016/02/03)
Palladium(0)-catalyzed carbocyclization of 1,7-enynes mediated by (chlorodimethylsilyl)pinacolborane proceeds with 1,8-addition of the silicon and boron functions to give functionalized cyclohexane derivatives with boron attached to the exocyclic olefin. A variety of chromane dervatives are accessible by this method. In contrast to the analogous reactions with 1,6-enynes, the configuration of the newly formed stereogenic center is controlled by a stereogenic center present in the substrate.
Gold-catalyzed rearrangement of allylic oxonium ylides: Efficient synthesis of highly functionalized dihydrofuran-3-ones
Fu, Junkai,Shang, Hai,Wang, Zhaofeng,Chang, Le,Shao, Wenbing,Yang, Zhen,Tang, Yefeng
supporting information, p. 4198 - 4202 (2013/05/08)
"Diazo" not needed: The title reaction results in the rearrangement of oxonium ylides, which were prepared from readily available homopropargylic allylic ethers instead of diazo compounds, through two different mechanisms: a concerted 2,3-sigmatropic rearrangement, or a stepwise 1,4-allyl migration followed by a Claisen rearrangement (see scheme). Copyright
Synthesis and cytotoxic activity of novel 2,6-disubstituted-4-mor- pholinothieno[3,2-d]pyrimidines as potent anti-tumor agents
Zhu, Wu Fu,Zhai, Xin,Li, Sai,Cao, Yun Yun,Gong, Ping,Liu, Ya Jing
scheme or table, p. 703 - 706 (2012/07/16)
A series of 2,6-disubstituted-4-morpholinothieno[3,2-d]pyrimidine derivatives were synthesized and their cytotoxic activity against H460, HT-29, MDA-MB-231, U87MG and H1975 cancer cell lines were evaluated in vitro. Most of the target compounds exhibited moderate to excellent activity to the tested cell lines. The most promising compound 23 (0.84 μmol/L, 0.23 μmol/L, 2.52 μmol/L, 1.80 μmol/L) was 1.0, 2.9, 29.3 and 4.3 times more active than GDC-0941 (0.87 μmol/L, 0.66 μmol/L, 73.8 μmol/L, 7.77 μmol/L) against H460, HT-29, MDA-MB-231 and U87MG cell lines, respectively.
Rhodium-catalyzed cycloisomerization involving cyclopropenes: Efficient stereoselective synthesis of medium-sized heterocyclic scaffolds
Miege, Frederic,Meyer, Christophe,Cossy, Janine
supporting information; experimental part, p. 5932 - 5937 (2011/08/02)
A happy medium: The title reaction of cyclopropenyl carbinols and carbinylamines gives carbo- and heterocycles with a [6.1.0] bicyclic ring fused to an aromatic ring (see scheme, Alloc=allyloxycarbonyl, Boc=tert- butyloxycarbonyl). These reactions are the first examples of the formation of medium-sized rings by the intramolecular cyclopropanation of an alkene with a donor-substituted rhodium carbenoid, which is not generated from a diazo compound.
A new domino-Knoevenagel-hetero-Diels-Alder reaction
Matiychuk, Vasyl S.,Lesyk, Roman B.,Obushak, Mykola D.,Gzella, Andrzej,Atamanyuk, Dmytro V.,Ostapiuk, Yuri V.,Kryshchyshyn, Anna P.
, p. 4648 - 4651 (2008/09/21)
Various novel 3,5a,6,11b-tetrahydro-2H,5H-chromeno[4′,3′:4,5]thiopyrano[2, 3-d][1,3]thiazol-2-ones were synthesized in 60-80% yields via domino-Knoevenagel-hetero-Diels-Alder reactions of 4-thioxo-1,3-thiazolidin-2-one with 3,7-dimethyl-6-octenal, 2-allyl
