6316-55-8Relevant academic research and scientific papers
Manipulating micellar environments for enhancing transition metal-catalyzed cross-couplings in water at room temperature
Lipshutz, Bruce H.,Ghorai, Subir,Leong, Wendy Wen Yi,Taft, Benjamin R.,Krogstad, Daniel V.
experimental part, p. 5061 - 5073 (2011/08/06)
The remarkable effects of added salts on the properties of aqueous micelles derived from the amphiphile PTS are described. Most notably, Heck reactions run in the presence of NaCl lead to couplings on aryl bromides in water at room temperature. Olefin cross- and ring-closing metathesis reactions run in the presence of small amounts of pH-lowering KHSO4 are also accelerated, another phenomenon that does not apply to typical processes in organic media. These salt effects allow, in general, for synthetically valuable C-C bond-forming processes to be conducted under environmentally benign conditions. Recycling of the surfactant is also demonstrated.
Catalytic enantioselective thioester aldol reactions that are compatible with protic functional groups
Magdziak, Derek,Lalic, Gojko,Lee, Hong Myung,Fortner, Kevin C.,Aloise, Allen D.,Shair, Matthew D.
, p. 7284 - 7285 (2007/10/03)
This communication reports highly enantioselective and diastereoselective methyl malonic acid half thioester (MeMAHT) aldol reactions that are compatible with protic functional groups and enolizable aldehydes, affording syn S-phenyl thiopropionates. Copyright
Enzymatic Desymmetrization of a Prochiral 1,3,5-Pentanetriol Derivative. Application to the Synthesis of a Cyanobacterial Heterocyst Glycolipid
Soriente, Annunziata,Laudisio, Giovanna,Giordano, Maurizio,Sodano, Guido
, p. 859 - 862 (2007/10/02)
(R)-3-t-butyldimethylsilyloxy-5-acetoxy-1-pentanol has been obtained by PFL catalyzed hydrolysis of the corresponding diacetate and has been utilized for the formal synthesis of the most widespread heterocyst glycolipid of N2-fixing cyanobacteria.
A general approach to enantiomerically pure methylcarbinols. Asymmetric synthesis of antibiotic (-)-A26771B and the WCR sex pheromone
Sinha,Sinha-Bagchi,Keinan
, p. 7789 - 7796 (2007/10/02)
Either (R) or (S) enantiomerically pure methylcarbinol groups are conveniently produced from monosubstituted alkenes via the Sharpless asymmetric dihydroxylation (AD) reaction. The initial AD product, 1,2- dihydroxyalkane, obtained with predictable absolute configuration and high enantiomeric purity, is converted into 2-acetoxy-1-bromoalkane and then subjected to reductive debromination. These conditions are compatible with a variety of functional groups, including acetal, ester, nitrile, ketone, and silyl ether. The advantages of this method are demonstrated by highly efficient, asymmetric syntheses of enantiomerically pure natural products. All four stereoisomers of the WCR sex pheromone 4 are prepared in six steps form nona-1,8-diene in 10-15% overall yield. Similarly, a highly efficient formal total synthesis of antibiotic (-)-A26771B (5) is accomplished via two alternative approaches. The first one transforms dodec-11-enal into enantiomerically pure 5 in 11 steps and 4.1% overall yield, while the second achieves the same transformation in 12 steps and 6.6% overall yield.
ALUMINA AS AN VERSATILE CATALYST FOR THE SELECTIVE ACETALIZATION OF ALDEHYDES
Kamitori, Yasuhiro,Hojo, Masaru,Masuda, Ryoichi,Yoshida, Tatsushi
, p. 4767 - 4770 (2007/10/02)
Alumina was found to be an effective and convenient catalyst for acetalization of aldehydes to the corresponding 1,3-dioxoranes and 1,3-dioxanes.It can be used for selective protection of only formyl group of ketoaldehydes.
SYNTHESIS OF SELENOACETALS
Clarembeau, M.,Cravador, A.,Dumont, W.,Hevesi, L,Krief, A.,et al.
, p. 4793 - 4812 (2007/10/02)
This paper reports our results concerning the syntheses of various bis(alkylseleno)alkanes and some of their arylseleno analogues by different methods.The scope and limitation of each of them are presented.
