Microwave-Assisted Synthesis of 2-Substituted 2-Thiazolines and 5,6-Dihydro-4H-1,3-thiazines
作者:Liliana R. Orelli、María C. Mollo、Juan A. Bisceglia、Natalia B. Kilimciler、Michele Mancinelli
DOI:10.1055/s-0039-1690822
日期:2020.6
An efficient and general method for the synthesis of 2-substituted thiazolines and 5,6-dihydro-4H-1,3-thiazines is developed via microwave-assisted ring closure of ω-thioamidoalcohols promoted by ethyl polyphosphate (PPE). The cyclization reaction involves an SN2-type mechanism and features the advantages of very short reaction times, high yields and a predictable stereochemical outcome. The acyclic
通过微波辅助聚磷酸乙酯(PPE)促进的ω-硫代酰胺醇的闭环反应,开发了一种高效且通用的合成2-取代的噻唑啉和5,6-二氢-4 H -1,3-噻嗪的方法。环化反应涉及S N 2型机理,具有反应时间短,产率高和可预测的立体化学结果的优点。无环前体是通过改进的二酰化-硫磺化-皂化顺序,从市售的ω-氨基醇中以高收率制备的。整个过程无金属且操作简单。
Facile Syntheses of Oxazolines and Thiazolines with <i>N</i>-Acylbenzotriazoles under Microwave Irradiation
作者:Alan R. Katritzky、Chunming Cai、Kazuyuki Suzuki、Sandeep K. Singh
DOI:10.1021/jo0355092
日期:2004.2.1
Microwave reactions of 2-amino-2-methyl-1-propanol (2) or 2-aminoethanethiol hydrochloride (4) with readily available N-acylbenzotriazoles 1a−j in the presence of SOCl2 produced 2-substituted 2-oxazolines 3a−j in 84−98% yields and 2-substituted thiazolines 5a−i in 85−97% yields, respectively. With use of this method chiral oxazoline 6, bisoxazoline 7, bisthiazoline 8, and 5,6-dihydro-4H-1,3-oxazines
在SOCl 2的存在下,2-氨基-2-甲基-1-丙醇(2)或2-氨基乙硫醇盐酸盐(4)与易于获得的N-酰基苯并三唑1a - j的微波反应产生了2-取代的2-恶唑啉3a - j分别以84-98%的产率和2-取代的噻唑啉5a - i的产率为85-97%。使用该方法时,手性恶唑啉6,双恶唑啉7,双噻唑啉8和5,6-二氢-4 H -1,3-恶嗪9或10还制备了82-96%的产率。这些结果证明了N-酰基苯并三唑在温和条件下和微波辐射下反应时间短的情况下在恶唑啉和噻唑啉制备中的新应用。
A one step synthesis of thiazolines from esters
作者:Carl A. Busacca、Yong Dong、Earl M. Spinelli
DOI:10.1016/0040-4039(96)00451-0
日期:1996.4
Condensation of the triisobutylaluminum complex of cysteamine HCl with a variety of carboxylic esters furnishes thiazolines in onestep. This new method has been applied to chiral α-aminoesters to give α-amino thiazolines of high optical purity, yet N-benzyl protection of the amine is required.
Asymmetric Hetero-Diels-Alder Reactions with Heterocumulenes
作者:Mark C. Elliott、Alexandra E. Monk、Elbertus Kruiswijk、David E. Hibbs、Robert L. Jenkins、David V. Jones
DOI:10.1055/s-1999-2853
日期:1999.9
Chiral 2-alkenyloxazolines and 2-alkenylthiazolines react with isocyanates and ketenes to give formal hetero-Diels-Alder adducts with complete diastereocontrol. In each case an electron-rich double bond in the adduct is prone to a second addition of the heterocumulene. In the case of the oxazoline adducts the second addition is faster than the first, while with thiazolines the second addition is slower
Photodimerisable polymer compositions are based upon derivatives of polyvinylalcohol and constituents of the formula:
wherein
m = 0 or 1;
n = 0 or an integer from 1-6; subject to the proviso that when n = 0, then m = 0;
b = H or a tertiary amine, methoxy or ethoxy group;
X = 0, S or Se or an NR₁ or C(R₁)₂ group,
wherein R₁ = H or an alkyl, hydroxyalkyl, aryl or aralkyl group,
Z = an anion and
wherein R₂ and R₃ are the same or different and each represents H, halogen or an alkyl, hydroxyalkyl, aryl, nitro or cyano group or R₂ and R₃ taken together may form part of the same aromatic or aliphatic ring system.
The preparation and typical uses of the polymer compositions as photostencils for screenprinting are also described.
可光聚合的聚合物组合物基于聚乙烯醇的衍生物和式中的成分:
其中
m = 0 或 1;
n = 0 或 1-6 之间的整数;但当 n = 0 时,则 m = 0;
b = H 或叔胺、甲氧基或乙氧基;
X = 0、S 或 Se 或 NR₁ 或 C(R₁)₂ 基团、
其中 R₁ = H 或烷基、羟烷基、芳基或芳烷基、
Z = 阴离子,且
其中 R₂ 和 R₃ 相同或不同,且各自代表 H、卤素或烷基、羟烷基、芳基、硝基或氰基,或 R₂ 和 R₃ 可共同构成同一芳香族或脂肪族环系的一部分。
此外,还介绍了聚合物组合物作为丝网印刷光模板的制备方法和典型用途。