Intramolecular and intermolecular diels-alder reactions of acylhydrazones derived from methacrolein and ethylacrolein
作者:Sylvia J. Allcock、Thomas L. Gilchrist、Stephen J. Shuttleworth、Frank D. King
DOI:10.1016/s0040-4020(01)96054-5
日期:1991.1
The intramolecular Diels-Alder reactions of hydrazones derivedfrom methacrolein or ethylacrolein and terminally unsaturated N-acyl-N-methylhydrazines have been investigated. The hydrazones 7b and 7c derivedfrom N-methyl-N-pent-4-enoylhydrazine 3b were found to undergo intramolecular [4 + 2] cycloaddition above 140 °C and the pyridopyridazines 12 were isolated. The corresponding hydrazones 8b and
作者:Mohammad Behforouz、Zhengxiang Gu、Lindsay S. Stelzer、Mohammad Ahmadian、Jalal Haddad、John A. Scherschel
DOI:10.1016/s0040-4039(97)00326-2
日期:1997.3
xy)-1-aza-1,3-butadienes 1 and 2 are prepared by the reaction of O-(t-butyldimethylsilyloxy)hydroxylamine with methyl vinyl ketone and methacrolein, respectively. Azadienes 1 and 2 through sharing of oxygen nonbonding electrons are activated and thus their Diels-Alder reactions with a number of halobenzoquinones, napthoquinones and N-phenylmaleimide regiospecifically give low to good yields of various
Diels-alder cycloaddition reactions of αβ-unsaturated aldehyde acylhydrazones
作者:Sylvia J. Allock、Thomas L. Gilchrist、Frank D. King
DOI:10.1016/s0040-4039(00)71235-4
日期:1991.1
Acylhydrazones derived from -methyl--pent-4-enoylhydrazine or -methyl--pent-4-ynoylhydrazine and αβ-unsaturated aldehydes undergo intramolecular Diels-Alder reactions at elevated temperatures. An intermolecular counterpart, the addition of methacrolein benzoylhydrazone to -phenylmaleimide, has also been carried out.