51029-29-9Relevant articles and documents
Oxidative cycloaddition of hydroxamic acids with dienes or guaiacols mediated by iodine(III) reagents
Shimizu, Hisato,Yoshimura, Akira,Noguchi, Keiichi,Nemykin, Victor N.,Zhdankin, Viktor V.,Saito, Akio
supporting information, p. 531 - 536 (2018/03/21)
[Bis(trifluoroacetoxy)iodo]benzene (BTI) and (diacetoxyiodo)benzene (DIB) efficiently promote the formation of acylnitroso species from hydroxamic acids in the presence of various dienes to give the corresponding hetero-Diels-Alder (HDA) adducts in moderate to high yields. The present method could be applied to the HDA reactions of acylnitroso species with o-benzoquinones generated by the oxidative dearomatization of guaiacols.
Cycloadditions of 1-phosphono-1,3-butadienes with nitroso heterodienophiles: A versatile synthetic route for polyfunctionalized aminophosphonic derivatives
Monbaliu, Jean-Christophe,Tinant, Bernard,Marchand-Brynaert, Jacqueline
experimental part, p. 5478 - 5486 (2010/11/05)
The hetero-Diels-Alder (HDA) reaction of 1-(diethoxyphosphonyl)-1,3- butadiene, 1-(dibenzyloxyphosphonyl)-1,3-butadiene, and 1-(diethoxyphosphonyl)- 3-tert-butyldimethylsilyloxy-1,3-butadiene with various nitroso heterodienophiles has been investigated as a new synthetic route for aminophosphonic derivatives. The HDA cycloadditions regioselectively led to the proximal isomers, i.e., presenting the NR3 group in the meta position regarding the phosphonate substituent. From the resulting 6-phosphono-3,6- dihydro-1,2-oxazine cycloadducts, a limited number of chemical steps were allowed to obtain a significant variety of aminophosphonic compounds of potential interest in medicinal chemistry. This has been illustrated through the synthesis of (Z)-4-(o-tolylamino)-1-hydroxybut-2-enylphosphonic acid, diethyl 3,4-dihydroxy-1-o-tolylpyrrolidin-2-yl-2-phosphonate, 4-(o-tolylamino)-1,2,3- trihydroxybutylphosphonic acid, diethyl 3-(2-(o-tolylamino)-1-hydroxyethyl) oxiran-2-yl-2-phosphonate, and diethyl 4,5-dihydroxymorpholin-6-yl-6- phosphonate.
Cycloadditions of nitrile oxides to amidoximes. A general synthesis of 3,5-disubstituted 1,2,4-oxadiazole-4-oxides
Quadrelli, Paolo,Invernizzi, Anna Gamba,Falzoni, Mario,Caramella, Pierluigi
, p. 1787 - 1796 (2007/10/03)
The cycloaddition of nitrile oxides to amidoximes is a general method for the synthesis of 3,5-disubstituted 1,2,4-oxadiazole-4-oxides with the same or different substituents. The yields are only moderate since an equivalent amount of the nitrile oxide is consumed by reaction with the amine released in the fragmentation of the primary cycloadducts and reforms the amidoxime. With excess nitrile oxides the 1,2,4-oxadiazole-4-oxides undergo a disproportionation reaction to yield nitroso carbonyl intermediates and 1,2,4-oxadiazoles.