5009-33-6Relevant articles and documents
A general approach to enantiomerically pure methylcarbinols. Asymmetric synthesis of antibiotic (-)-A26771B and the WCR sex pheromone
Sinha,Sinha-Bagchi,Keinan
, p. 7789 - 7796 (1993)
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.
Cyclopropanation of Terminal Alkenes through Sequential Atom-Transfer Radical Addition/1,3-Elimination
Tappin, Nicholas D. C.,Michalska, Weronika,Rohrbach, Simon,Renaud, Philippe
supporting information, p. 14240 - 14244 (2019/08/26)
An operationally simple method to affect an atom-transfer radical addition of commercially available ICH2Bpin to terminal alkenes has been developed. The intermediate iodide can be transformed in a one-pot process into the corresponding cyclopropane upon treatment with a fluoride source. This method is highly selective for the cyclopropanation of unactivated terminal alkenes over non-terminal alkenes and electron-deficient alkenes. Due to the mildness of the procedure, a wide range of functional groups such as esters, amides, alcohols, ketones, and vinylic cyclopropanes are well tolerated.
Aerobic Acetoxyhydroxylation of Alkenes Co-catalyzed by Organic Nitrite and Palladium
Chen, Xian-Min,Ning, Xiao-Shan,Kang, Yan-Biao
, p. 5368 - 5371 (2016/11/02)
An aerobic acetoxyhydroxylation of alkenes cooperatively catalyzed by organic nitrite and palladium at room temperature using clean and cheap air as the sole oxidant has been developed. Various vicinal diols, diacetoxyalkanes, and dihalogenoalkanes have been synthesized. The gram-scale synthesis has also been approached. Vicinal difluorination and dichlorolation products have also been achieved via this reaction.