Autor: Michal Sobkowski (msob_at_ibch.poznan.pl)
Data: Mon 11 Mar 2002 - 12:44:45 MET
At 15:21 04.03.02, Jerzy Peszke wrote:
>Poszukuje informacji o reakcjach Dielsa-Aldera: retro
>i domino.
Z Beilsteina po jednym trafieniu na "Domino/Retro Diels-Alder reactions":
Authors: Sander, Michael; Dehmlow, Eckehard Volker
Journal Title: Eur.J.Org.Chem.
Number: 2
Publication Year: 2001
Page: 399 - 404
Title: Synthesis of a Substituted Bi[cyclohepta-3,5(3',5')-dienyl]: A
Possible Building Block for Domino Diels-Alder Reactions
Abstract: A versatile 13-step synthesis of
1,1'-dimethoxy-4,4'5,5'-tetrakis(trimethylsilyloxy)bicyclohepta-3,3'5,5'-dienyl
(11) is described. 11 represents a potential building block for the
construction of polycyclic cage compounds through domino Diels-Alder and
pincer reactions.
Keywords: Domino Diels-Alder reactions; Pincer reactions; Substituted
1,1'-dihydroxybi(cycloheptadienyl)/McMurry reactions
Authors: Klaerner, Frank-Gerrit; Breitkopf, Volker
Journal Title: Eur.J.Org.Chem.
Number: 11
Publication Year: 1999
Page: 2757 - 2762
Title: The Effect of Pressure on Retro Diels-Alder Reactions
Abstract: The activation and reaction volumes ($DV(excit.)/$DV) were
determined for the retro Diels-Alder reactions of the parent
dihydrobarrelene 1a, its 2-cyano derivative 1b, the exo and endo
Diels-Alder adducts of maleic anhydride to naphthalene exo-, endo-4, and
the exo and endo Diels-Alder adducts of N-phenylmaleic imide to
6,6-dimethylfulvene exo-, endo-8 from the pressure dependence of the rate
constants and the partial molar volumes (V) of reactants and products at
various temperatures. The cleavage of exo-4, endo-4, and exo-8 are slightly
accelerated by pressure showing negative volumes of activation
($DV(excit.)<0) whereas the others are slightly retarded ($DV(excit.)>0).
From the analysis of the volume data including the van der Waals volumes
(V&W%) one can conclude that the packing coefficients of the pericyclic
transition states are equal to or even larger than those of the
corresponding Diels-Alder adducts. This finding may be explained with the
restriction of the degrees of freedom in the transition states leading to a
contraction of the expansion volume.
Keywords: High-pressure chemistry; Activation volumes; Reaction
volumes; Packing coefficients; Retro Diels-Alder reactions
Pozdrawiam,
Michał
--
dr Michał Sobkowski
Instytut Chemii Bioorganicznej PAN, Poznań
http://www.man.poznan.pl/private/users/msob.html
To archiwum zostało wygenerowane przez hypermail 2.1.7 : Thu 08 May 2003 - 14:50:53 MET DST