Quantum Chemical Analysis and Experimental Study of the Cycloaddition Reaction between Aminoacetylenes and 6-Nitroindolizines. NMR and ab Initio Evidence for the [4+2] Adduct Formation
摘要:
7-Methyl-6-nitro-2-phenylindolizine (Ia) reacts with 1-(diethylamino)-2-methylacetylene (IIa) giving 1:1 cycloadduct IIIa and not the expected product of dipolar [8+2] cycloaddition cyclazine IVa. According to NMR data the structure of IIIa consists of 1,2-oxazine fragment corresponding to the [4+2] cycloaddition of the acetylene to the sequence C(5)-C(6)-N-O of nitroindolizine. The mechanism of model reactions between nitroindolizine We and aminoacetylenes IIb,c is studied by an ab initio and AM1 method. Results of calculations indicate that the initially formed zwitterionic intermediates may undergo further ring closure either to cycl[3.2.2]azines IVb,c or 1,2-oxazine cycloadducts IIIb,c. Although the structures TV are lower in energy than III, the activation barrier for the formation of III is smaller than the barrier leading to IV.
Compositions de teinture des fibres kératiniques contenant des dérives d'indolizine et procédé de teinture
申请人:L'OREAL
公开号:EP1129691A2
公开(公告)日:2001-09-05
L'invention a pour objet une composition pour la teinture d'oxydation des fibres kératiniques contenant au moins un dérivé d'indolizine à titre de coupleur et au moins une base d'oxydation.
L'invention a également pour objet l'utilisation de dérivés d'indolizine à titre de coupleur pour la teinture d'oxydation des fibres kératiniques en association avec au moins une base d'oxydation, ainsi que les procédés de teinture les mettant en oeuvre.
Indolizine derivatives, compositions comprising at least one coupler chosen from indolizine derivatives and at least one oxidation base, and methods for using same
申请人:——
公开号:US20020002749A1
公开(公告)日:2002-01-10
Compositions for oxidation dyeing of keratin fibers comprising at least one oxidation base and at least one coupler chosen from indolizine derivatives, methods for using the same for oxidation dyeing of keratin fibers, and compounds chosen from indolizine derivatives.