微波辅助合成2-芳基-2-恶唑啉,5,6-二氢-4 H -1,3-恶嗪和4,5,6,7-四氢-1,3-恶氮杂s
摘要:
提出了通过微波辅助多磷酸(PPA)酯促进的ω-氨基醇的环化反应合成5至7元环亚氨基醚的第一个通用程序。使用聚磷酸乙酯/ CHCl 3有效地制备了2-芳基-2-恶唑啉和5,6-二氢-4 H -1,3-恶嗪。在无溶剂条件下,多磷酸三甲基甲硅烷基酯可合成迄今未报道的4,5,6,7-四氢-1,3-氧杂氮杂pine。该方法具有良好的收率和优异的收率,并且反应时间短。在手性底物中研究了PPA酯的反应机理和作用。
Hydrogen Bond Organocatalysis of Benzotriazole in Transamidation of Carboxamides with Amines
作者:Thanh Binh Nguyen、Ali Al-Mourabit、Ludmila Ermolenko、Marie-Elise Tran Huu Dau
DOI:10.3987/com-13-s(s)41
日期:——
systems (ring-opening of four-membered rings; (ii) intramolecular assistance, or both factors); (iii) use of moisture-sensitive and/or activation reagents (up to 2–3 equivalents; borate esters, dialkylformamide dialkyl acetals, AlCl3, AlMe3, HCl). Examples of transamidation from the Stahl's group provided an elegant possibility of preparing amides under mild † This paper is dedicated to Prof. Victor
Microwave-Assisted Synthesis of 2-Aryl-2-oxazolines, 5,6-Dihydro-4<i>H</i>-1,3-oxazines, and 4,5,6,7-Tetrahydro-1,3-oxazepines
作者:María C. Mollo、Liliana R. Orelli
DOI:10.1021/acs.orglett.6b03122
日期:2016.12.2
general procedure for the synthesis of 5- to 7-membered cyclic iminoethers by microwave-assisted cyclization of ω-amido alcohols promoted by polyphosphoric acid (PPA) esters is presented. 2-Aryl-2-oxazolines and 5,6-dihydro-4H-1,3-oxazines were efficiently prepared using ethyl polyphosphate/CHCl3. Trimethylsilyl polyphosphate in solvent-free conditions allowed for the synthesis of hitherto-unreported
提出了通过微波辅助多磷酸(PPA)酯促进的ω-氨基醇的环化反应合成5至7元环亚氨基醚的第一个通用程序。使用聚磷酸乙酯/ CHCl 3有效地制备了2-芳基-2-恶唑啉和5,6-二氢-4 H -1,3-恶嗪。在无溶剂条件下,多磷酸三甲基甲硅烷基酯可合成迄今未报道的4,5,6,7-四氢-1,3-氧杂氮杂pine。该方法具有良好的收率和优异的收率,并且反应时间短。在手性底物中研究了PPA酯的反应机理和作用。
Metal-Free <i>O</i>
-Selective Direct Acylation of Amino Alcohols Through Pseudo-Intramolecular Process
Acylation of diamines using α‐aryl‐β‐keto esters occurs regioselectively at the less hindered amino group. The transacylation using N‐alkylamino alcohol resulted in chemoselective O‐acylation in the absence of metal catalyst. Protection of the amino group is not necessary. These reactions proceed efficiently because of the pseudo‐intramolecular process.