174132-33-3Relevant articles and documents
Di- and triarylmethylium ions as probes for the ambident reactivities of carbanions derived from 5-benzylated Meldrum's acid
Chen, Xi,Tan, Yue,Berionni, Guillaume,Ofial, Armin R.,Mayr, Herbert
supporting information, p. 11069 - 11077 (2014/10/15)
The kinetics of the reactions of carbocations with carbanions 1 derived from 5-benzyl-substituted Meldrum's acids 1-H (Meldrum's acid=2,2-dimethyl-1,3- dioxane-4,6-dione) were investigated by UV/Vis spectroscopic methods. Benzhydryl cations Ar2CH+ added exclusively to C-5 of the Meldrum's acid moiety. As the second-order rate constants (kC) of these reactions in DMSO followed the linear free-energy relationship lg k=s N(N+E), the nucleophile-specific reactivity parameters N and s N for the carbanions 1 could be determined. In contrast, trityl cations Ar3C+ reacted differently. While tritylium ions of low electrophilicity (E-2) reacted with 1 through rate-determining β-hydride abstraction, more Lewis acidic tritylium ions initially reacted at the carbonyl oxygen of 1 to form trityl enolates, which subsequently reionized and eventually yielded triarylmethanes and 5-benzylidene Meldrum's acids by hydride transfer.
Efficient synthesis of halo indanones via chlorosulfonic acid mediated Friedel-Crafts cyclization of aryl propionic acids and their use in alkylation reactions
Sharma, Anil K.,Subramani, Amutha V.,Gorman, Christopher B.
, p. 389 - 395 (2007/10/03)
Several halo indanones were synthesized from benzyl Meldrum's acid derivatives in two steps. Although several Lewis acids are effective for the Friedel-Crafts ring-closing reaction on more electron-rich arenes, in the case of the electron-deficient arenes this chemistry is not efficient. Here it is reported that chlorosulfonic acid (used as solvent) is an efficient reagent for cyclization of electron-withdrawing arenes. These molecules are potentially useful for subsequent alkylation reactions. The selective alkylation of 5,7-dibromo indanone is demonstrated using Pd-catalyzed Grignard coupling to provide monoalkylated indanone in good yield.
Malonic acid derivatives, processes for their preparation, for their use and pharmaceutical compositions containing them
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, (2008/06/13)
New compounds for the inhibition of blood clotting proteins, and more particularly, to malonic acid derivatives of the formula I, wherein R(1), R(2), R(3), R(4), R(5), and R(6) have the meanings indicated in the claims. The compounds of formula I are inhibitors of the blood clotting enzyme factor Xa. Processes for the preparation of the compounds of formula I, methods of inhibiting factor Xa activity and of inhibiting blood clotting, use of the compounds of formula I in the treatment and prophylaxis of diseases, which can be treated or prevented by the inhibition of factor Xa activity such as thromboembolic diseases, and use of the compounds of formula I in the preparation of medicaments to be applied in such diseases. Compositions containing a compound of formula I in admixture or otherwise in association with an inert carrier, in particular pharmaceutical compositions containing a compound of formula I together with pharmaceutically acceptable carrier substances and auxiliary substances.
