127322-74-1Relevant academic research and scientific papers
Multigramme synthesis and asymmetric dihydroxylation of a 4-fluorobut-2E-enoate
Laurenson, James A. B.,Parkinson, John A.,Percy, Jonathan M.,Rinaudo, Giuseppe,Roig, Ricard
, p. 2660 - 2668 (2013)
Esters of crotonic acid were brominated on a multigramme scale using a free radical procedure. A phase transfer catalysed fluorination transformed these species to the 4-fluorobut-2E-enoates reproducibly and at scale (48-53%, ca. 300 mmol). Asymmetric dihydroxylation reactions were then used to transform the butenoate, ultimately into all four diastereoisomers of a versatile fluorinated C4 building block at high enantiomeric-enrichment. The (DHQ) 2AQN and (DHQD)2AQN ligands described by Sharpless were the most effective. The development and optimisation of a new and facile method for the determination of ee is also described; 19F{1H} spectra recorded in d-chloroform/diisopropyl tartrate showed distinct baseline separated signals for different enantiomers.
Access to Polyfunctionalized Chiral Piperidines through Enantioselective Addition-Carbocyclization Cascade Reaction Catalyzed by a Rhodium(I)-Diene Complex
Serpier, Fabien,Brayer, Jean-Louis,Folléas, Beno?t,Darses, Sylvain
, p. 5496 - 5499 (2015)
A new addition-carbocyclization cascade reaction initiated by arylboronic acids and catalyzed by a rhodium/chiral diene complex is described. Starting from N-bridged oxoenoate derivatives, highly functionalized piperidines bearing three contiguous stereogenic centers were obtained with excellent enantio- and diastereoselectivities.
Asymmetric rhodium-catalysed addition of arylboronic acids to acyclic unsaturated esters containing a basic γ-amino group
Anderson, Niall A.,Fallon, Brendan J.,Valverde, Elena,MacDonald, Simon J. F.,Pritchard, John M.,Suckling, Colin J.,Watson, Allan J. B.
, p. 2817 - 2821 (2013/02/21)
Application of the Miyaura-Hayashi rhodium-catalysed addition of aryl boronic acids to acyclic unsaturated esters featuring basic centres to yield γ-amino butyric acids incorporating a substituted β-phenyl group is described. Unoptimised isolated yields and enantiomeric excesses vary from moderate to excellent, and the method tolerates a variety of substitution patterns and a range of functionality. Copyright
Synthesis and herbicidal activity of diphenyl ether derivatives containing unsaturated carboxylates
Yu, Haibo,Yang, Huibin,Cui, Dongliang,Lv, Liang,Li, Bin
scheme or table, p. 11718 - 11726 (2012/04/04)
A series of novel diphenyl ether derivatives containing unsaturated carboxylates were designed and synthesized. Their structures were identified by 1H nuclear magnetic resonance and elemental analyses. The bioassays indicated that the compounds 5b and 5c exhibited good herbicidal activities against velvetleaf at a concentration of 30-40 g/hm2. The relationship between structure and herbicidal activity was also discussed. Among unsaturated carboxylates group, butenoate is the most promising one. Amonst them, 4-ethoxy-4-oxobutenyl 5-(2-chloro-4-(trifluoromethyl)phenoxy)-2- nitrobenzoate 5b was identified as the most promising candidate due to its high protoporphyrinogen IX oxidase inhibition effect (pI50 = 6.64) and good herbicidal activity against broadleaf weeds with selectivity to soybean and low toxicity to mammals.
