CO<sub>2</sub>/Photoredox-Cocatalyzed Tandem Oxidative Cyclization of α-Bromo Ketones and Amines To Construct Substituted Oxazoles
作者:Xiaowei Zhang、Yonghui He、Jing Li、Rui Wang、Lijun Gu、Ganpeng Li
DOI:10.1021/acs.joc.9b00283
日期:2019.6.21
CO2/photoredox-cocatalyzed tandem oxidative cyclization of α-bromo ketones and amines for the preparation of substituted oxazoles has been achieved. The avoidance of using both transition-metal catalysts and peroxides makes this method more sustainable and renewable.
Development of a method for the synthesis of 2,4,5-trisubstituted oxazoles composed of carboxylic acid, amino acid, and boronic acid
作者:Kohei Yamada、Naoto Kamimura、Munetaka Kunishima
DOI:10.3762/bjoc.13.146
日期:——
A novel method for the synthesis of trisubstituted oxazoles via a one-pot oxazole synthesis/Suzuki-Miyaura coupling sequence has been developed. One-pot formation of 5-(triazinyloxy)oxazoles using carboxylic acids, amino acids and a dehydrative condensingreagent, DMT-MM, followed by Ni-catalyzed Suzuki-Miyaura coupling with boronic acids provided the corresponding 2,4,5-trisubstituted oxazoles in
Alkynyl Thioethers in Gold-Catalyzed Annulations To Form Oxazoles
作者:Raju Jannapu Reddy、Matthew P. Ball-Jones、Paul W. Davies
DOI:10.1002/anie.201706850
日期:2017.10.16
regioselective, and convergent access to densely functionalized oxazoles is realized in a functional-group tolerant manner using alkynylthioethers. Sulfur-terminated alkynes provide access to reactivity previously requiring strong donor-substituted alkynes such as ynamides. Sulfur does not act in an analogous donor fashion in this gold-catalyzed reaction, thus leading to complementary regioselective outcomes
One-Pot Friedel−Crafts/Robinson−Gabriel Synthesis of Oxazoles Using Oxazolone Templates
作者:Manasi Keni、Jetze J. Tepe
DOI:10.1021/jo0501590
日期:2005.5.1
We report herein a one-potsynthesis of 2,4,5-trisubstituted oxazoles via a Friedel−Crafts/Robinson−Gabriel synthesisusing a general oxazolone template. Treatment of the oxazolone template with a range of aromatic nucleophiles provided the highly substituted oxazoles in good yields.
Practical oxazole synthesis mediated by iodine from α-bromoketones and benzylamine derivatives
作者:Wen-Chao Gao、Ruo-Lin Wang、Chi Zhang
DOI:10.1039/c3ob41566j
日期:——
system of I2/K2CO3 could efficiently promote the oxazole synthesis from α-bromoketones and benzylamine derivatives in DMF. This method was not only suitable for 2,5-diaryl oxazole synthesis but also for 2,4,5-trisubstituted oxazole and 5-alkyl/alkenyl oxazole synthesis. Furthermore, this method was successfully applied to a one-step synthesis of a natural product halfordinol in 62% yield.
I 2 / K 2 CO 3试剂体系可有效促进DMF中α-溴代酮和苄胺衍生物的恶唑合成。该方法不仅适用于2,5-二芳基恶唑的合成,而且适用于2,4,5-三取代的恶唑和5-烷基/烯基恶唑的合成。此外,该方法已成功地以62%的收率成功地一步合成了天然产物Halfordinol。