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Алкилирование енаминов, бета-дикетонов и енаминокетонов

from cyclohexane-1,3-dione  may  be  controlled  by  the
nature  of  the  base  used.Our  results  indicate  that  monoalkylation  is
completely regioselective; lithium diisopropylamide  leads  to  ?’-alkylated
compounds  while  lithium   bis(trimethylsilyl)amide   affords   ?-alkylated
products.In contrast, alkylation of ?’- or  ?-substituted  compounds  always
occurs in the ?’-position regardless of the base.

     Regiospecificity and Regioselectivity of the Alkylation, Acylation,
          Sulfenylation and Sulfonylation of Pyrrolidine Enaminones

  Thomas Burgemeister; Gerd Dannhardt; Ernst Eibler; Brigitte Paulus; Klaus

 Source details:               Arch.Pharm.(Weinheim Ger.) 1988, 321  :  345-
 Document type:             Journal
 CODEN:                         ARPMAS
 Language:                       GE
 CNR:                              5807249


 Different methods to modify a pyrrolidine  enaminone  regiospecifically  or
regioselectively at the  N-  and  C-atom,  respectively,  are  described.All
compounds have been isolated and characterized, in case  of  the  alkylation
reactions the ratio of regioisomers is determined  by  HPLC.NOE  experiments
are performed in order to prove the configuration of some adducts.

 Reactivity of N-substituted enaminones with unsaturated carbonyl compounds
   Esther Caballero; Blanca Madrigal; Manuel Medarde; Pilar Puebla; Zoila
                               Honores; et al.

 Source details:               Ach.Mod.Chem. 1998, 135 : 4 457-474.
 Document type:             Journal
 CODEN:                        ACMCEI
 Language:                    EN
 CNR:                            6101721
 The reactivity  of  enaminones  of  2-aminoethanol  and  2-aminoethanothiol
towards polyelectrophilic reagents has been studied.A brief overview of  our
previous results with this enaminones, which  allowed  us  to  describe  new
synthesis of fused heterocycles, is included. In the present work, only  the
formation of C-C bond is a  common  feature  of  the  reaction,  to  produce
derivatives or  simple  heterocycles.Although  no  fused  heterocycles  were
obtained, the reaction products have complex  functionalization  which  will
allow further cyclization to such a class of polyfused systems.

 Reactions between Enaminones and Enones. Part 2. C versus N-Alkylation with
   Cyclohex-2-enone. Structure Confirmation by Reduction of a Dienaminone
                   Derivative of Dehydrated Dimedone Dimer

              Ibrahim Chaaban; John V. Greenhill; Mohamed Ramli

 Source details:             J.Chem.Soc.Perkin Trans.1 1981, 3120-3124.
 Document type:            Journal
 CODEN:                     JCPRB4
 Language:                    EN
 CNR:                            5625982
  Primary  and  secondary  enaminones  derived  from  cyclohexane-1,3-dione,
dimedone, and acetylacetone react with cyclohexenone to give exclusively  C-
alkylated derivatives.In every case the products form  carbinolamines  which
exist  as  1-hydroxy-2-azacyclo[3.3.1]nonenes.This  was  confirmed  in  some
examples by formation of an extra ring between nitrogen and oxygen.A  series
of dienaminones were  prepared  from  2-(5,5-dimethyl-3-oxocyclohex-1-enyl)-
5,5-dimethylcyclohexane-1,3-dione and one of these was reduced  to  give  an
azanonene identical with that from C-alkylation.

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Алкилирование енаминов, бета-дикетонов и енаминокетонов


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