Studies on [2 + 3] cycloaddition reaction of nitrile oxides to linear dipolarophiles bearing multiple double bonds
作者:Mirosław Gucma、W. Marek Gołębiewski、Alicja Katarzyna Michalczyk
DOI:10.1007/s00706-016-1797-4
日期:2016.10
selectivity, regioselectivity, and stereoselectivity of [2 + 3] cycloaddition of benzonitrile oxides to polyunsaturated esters were examined. Site selectivity was correlated with electron charges of unsaturated carbon atoms. Structure of the products has been established by an extensive application of 1H and 13C NMR spectroscopy and electrospray ionization mass spectrometry. Graphical abstract
摘要研究了苄腈氧化物与多不饱和酯的[2 + 3]环加成反应的位点选择性,区域选择性和立体选择性。位点选择性与不饱和碳原子的电子电荷相关。产品的结构已通过1 H和13 C NMR光谱学和电喷雾电离质谱的广泛应用而建立。 图形概要
One-Pot Synthesis of Isoxazolines from Aldehydes Catalyzed by Iodobenzene
作者:Jie Yan、Liuquan Han、Bijun Zhang、Changbin Xiang
DOI:10.1055/s-0033-1340464
日期:——
finally, a 1,3-dipolarcycloaddition between the nitrileoxides and alkenes occurs to provide the isoxazolines in moderate to good yields. A convenient one-pot, three-step procedure for the synthesis of isoxazolines starting from aldehydes has been developed involving catalytic cycloaddition between nitrileoxides and alkenes, in which iodobenzene is used as the catalyst for the in situgeneration of a hypervalent
1,3-Dipolar Cycloaddition Reaction of Nitrile Oxides Revisited-Unusual Side Products Characterized by 2D NMR
作者:M. Gucma、W. M. Gołębiewski
DOI:10.1002/jhet.1792
日期:2014.5
Cycloaddition of (4‐trifluoromethyl)phenylnitrile oxide to N‐(4‐methoxyphenyl)acrylamide afforded bicyclic tetrahydro‐oxazolo‐(3,2‐b)[1,3]oxazine‐2‐carboxamide derivative in result of N‐acylation of the initially formed cycloadduct by the dipolarophile. 2:1 Cycloaddition of the same dipole to N‐(4‐methoxyphenyl)crotonamide yielded dihydro[1,2]‐oxazolo[2,3‐d][1,2,4]oxadiazole‐7‐carboxamide because of
(4-三氟甲基)苯腈氧化物与N-(4-甲氧基苯基)丙烯酰胺的环加成反应可得到双环四氢-恶唑并(3,2- b)[1,3]恶嗪-2-羧酰胺衍生物,这是由于N-酰化了最初由双极性亲和剂形成环加合物。2:1将同一偶极环加成至N-(4-甲氧基苯基)巴豆酰胺可产生二氢[1,2]-恶唑并[2,3- d ] [1,2,4]恶二唑-7-羧酰胺,因为第二次加成偶极与第一个形成的2-异恶唑啉化合物的C═N键的关系。产品的结构已通过1D和2D NMR光谱的广泛应用得以阐明。
Enantioselective 1,3-dipolar cycloaddition reactions using chiral lanthanide catalysts
作者:W. Marek Gołȩbiewski、Mirosław Gucma
DOI:10.1002/jhet.5570450620
日期:2008.11
Regio- and stereoselective 1,3-dipolarcycloaddition of nitrile oxides to internal 2-pentenols, α,β-unsaturated esters and amides catalyzed by R-(+) BINOL-lanthanide complexes affords corresponding 3-aryl-2-isoxazolines with enantioselectivities up to 89% ee.
R -(+)BINOL-镧系元素配合物催化的腈氧化物与内在的2-戊烯醇,α,β-不饱和酯和酰胺的区域和立体选择性1,3-偶极环加成反应提供了对映选择性最高的相应的3-芳基-2-异恶唑啉到89%ee。
Studies on the [2+3] cycloaddition reaction of nitrile oxides to abietic acid esters
[2+3] Dipolar cycloadditions of aromatic nitrileoxides to abietic acid esters were investigated. The reactions showed complete site selectivity and regioselectivity, while the stereoselectivity depended on the structures of the dipolarophiles.