Assignment of configurations to adducts of 2-substituted anthracene with maleic anhydride by N.M.R. spectroscopy

1976 ◽  
Vol 29 (6) ◽  
pp. 1215 ◽  
Author(s):  
SM Verma ◽  
RM Singh
Keyword(s):  
Maleic Anhydride ◽  
Phenyl Group ◽  
Diels Alder ◽  
Amino Group ◽  
Restricted Rotation ◽  
Magnetic Effects ◽  
Anti Conformation ◽  
Diagnostic Probe

Isomeric adducts of 2-methylanthracene and maleic anhydride and of 2-aminoanthracene and maleic anhydride were prepared and their configurations determined by N.M.R. spectroscopy. The adducts were transformed into their N-aminoimide derivatives. N'-Substituents on the amino group were chosen so as to permit, because of their restricted rotation and non-planarity about the N-N' bond, an investigation into the magnetic effects of the cage moiety. When both the dienyl parts of the Diels-Alder adducts are almost identical, the N'-acetyl-N'-phenyl group has been found to be a diagnostic probe for the configurational studies. In N-(N'-acetyl-N'-aroy1amino)imide derivatives, the N'-aroyl group has been found to prefer an anti conformation while in the N?-acetyl- N'-phenyl group the N'-phenyl prefers the syn conformation.

Products of reaction between styrene and some radicals with 2,2-diphenyl-1-picrylhydrazyl

1981 ◽  
Vol 59 (21) ◽  
pp. 3095-3104 ◽  
Author(s):  
Karl R. Kopecky ◽  
Michael C. Hall
Keyword(s):  
Nitro Group ◽  
Considerable Increase ◽  
Phenyl Group ◽  
Diels Alder ◽  
Benzyl Radicals ◽  
Products Of Reaction ◽  
Cis And Trans

Addition of 2,2-diphenyl-1-picrylhydrazyl DPPH to styrene at 75 °C results in little change in the amounts of cis- and trans-1,2-diphenylcyclobutane and 1,2,3,4-tetrahydro-1-phenylnaphthalene, in a slightly smaller amount of 1-phenylnaphthalene, and in a considerable increase in the amount of 1,2-dihydro-1-phenylnaphthalene that are formed. Formation of the styrene trimer 1,2,3,4-tetrahydro-1-phenyl-4-(1-phenylethyl)naphthalene is eliminated completely. Products derived from DPPH are l-(4-nitro-phenyl)-1-phenyl-2-picrylhydrazine 9 and 1-[2,6-dinitro-4-(1,2,3,4-tetrahydro-4-phenyl-1-naphthyl)phenyl]-2,2-diphenylhydrazine, 10. DPPH intercepts the thermally formed Diels–Alder dimer of styrene as soon as it is formed to give the 1,2,3,4-tetrahydro-4-phenyl-1-naphthyl radical.Thermolysis of bis(1,2,3,4-tetrahydro-4-phenyl-1-naphthyl)diazene in the presence of DPPH yields 20% of 10, 10,% of l-[2,6-dinitro-4-(1,2,3,4-tetrahydro-4-phenyl-1-naphthyl)phenyl]-2-(4-nitrophenyl)-2-phenylhydrazine and 9 while thermolysis of 1,2-bis(1-phenylethyl)diazene in the presence of DPPH yields 9 and 44% of 1-[2,6-dinitro-4-(1-phenylethyl)phenyl]-2,2-diphenyl-hydrazine showing that substituted benzyl radicals efficiently displace the 4-nitro group of DPPH. The nitro group is transferred to an unsubstituted phenyl group of DPPH.

Hetero-Diels-Alder Reactions of Enaminothione with Electrophilic Olefins. Synthesis of 2-Furyl Substituted 2H-Thiopyrans

2002 ◽  
Vol 57 (6) ◽  
pp. 637-644 ◽  
Author(s):  
Krystyna Bogdanowicz-Szwed ◽  
Artur Budzowski
Keyword(s):  
Acetic Acid ◽  
Maleic Anhydride ◽  
Acetic Anhydride ◽  
Alder Reaction ◽  
Diels Alder ◽  
Diethyl Maleate ◽  
Diels Alder Reaction

AbstractThe hetero-Diels-Alder reaction of 1-(2-furyl)-3-(dimethylamino)-2-propene-1-thione (diene) with maleic and fumaric acids, and β-nitrostyrenes yielded 3,4-dihydro-2H-thiopyran derivatives. Treatment of some of those cycloadducts with acetic acid caused elimination of dimethylamine yielding stable 2H-thiopyrans. Reaction of the diene with maleic anhydride furnished a cycloadduct which underwent spontaneous rearrangement to form an N,N-dimethylamide derivative. Cycloadditions of the diene to maleimide, N-phenylmaleimide, diethyl maleate, fumarate and butenolide, carried out in the presence of acetic anhydride,were followed by elimination of dimethylamine, afforded stable 2H-thiopyran derivatives.

Reply to Comment on “Kinetics of a Diels−Alder Reaction of Maleic Anhydride and Isoprene in Supercritical CO2”

2003 ◽  
Vol 107 (43) ◽  
pp. 9249-9249 ◽  
Author(s):  
Evgeni M. Glebov ◽  
Larisa G. Krishtopa ◽  
Victor Stepanov ◽  
Lev N. Krasnoperov
Keyword(s):  
Maleic Anhydride ◽  
Supercritical Co2 ◽  
Alder Reaction ◽  
Diels Alder ◽  
Diels Alder Reaction ◽  
Kinetics Of
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