73718-09-9Relevant articles and documents
Direct synthesis of 3-arylpropionic acids by tetraphosphine/palladium catalysed Heck reactions of aryl halides with acrolein ethylene acetal
Lemhadri, Mhamed,Doucet, Henri,Santelli, Maurice
, p. 11533 - 11540 (2007/10/03)
Through the use of [PdCl(C3H5)]2/Cis,cis, cis-1,2,3,4-tetrakis(diphenylphosphinomethyl)cyclopentane as a catalyst, a range of aryl bromides undergoes Heck reaction with acrolein ethylene acetal. With this acetal, the selective formation of 3-arylpropionic acids/esters was observed. The functional group tolerance on the aryl halide is remarkable; substituents such as fluoro, methyl, methoxy, acetyl, formyl, benzoyl, nitro or nitrile are tolerated. Furthermore, this catalyst can be used at low loading, even for reactions of sterically hindered aryl bromides. Graphical Abstract.
Process for the preparation of carboxylic acids and derivatives of them
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, (2008/06/13)
The subject matter of the invention is a process for the preparation of carboxylic acids and derivatives of them of the general formula STR1 wherein R means hydrogen, or a C1-4 alkyl or a (C1-5 alkoxy)carbonyl group, R1 is as defined in claim 1, R7 stands for hydrogen or a C1-7 alkyl group and R8 means hydrogen or a carboxyl group, by reacting a 1,3-dioxane-4,6-dione derivative of the general formula STR2 wherein R9 stands for a C1-4 alkyl group or a phenyl group, optionally monosubstituted by halogen and R10 stands for hydrogen or a C1-5 alkyl group or R9 and R10 together form a pentamethylene group, and an aldehyde or ketone of the general formula STR3 in the presence of formic acid.
LONG-RANGE EXCITON COUPLING FROM DIPYRRINONE CHROMOPHORES
Byun, Young-Seok,Lightner, D. A.
, p. 9759 - 9772 (2007/10/02)
Dipyrrinone chromophores, attached by their acid termini to give (1R,2R)-cyclohexanediol dipropionate and diacetate esters (xanthobilirubinate and nor-xanthobilirubinate, respectively), interact through exciton coupling, as evidenced by intense bisignate