Anti-Selective Epoxidation of Methyl α-Methylene-β-<i>tert</i>-butyldimethylsilyloxycarboxylate Esters. Evidence for Stereospecific Oxygen Atom Transfer in a Nucleophilic Epoxidation Process
作者:Jakub Švenda、Andrew G. Myers
DOI:10.1021/ol900665a
日期:2009.6.4
Methyl α-methylene-β-tert-butyldimethylsilyloxycarboxylate esters are found to undergo diastereoselective epoxidation in the presence of potassium tert-butoxide−tert-butyl hydroperoxide to form anti products. In an effort to better understand mechanistic details of the transformation and the basis of diastereoselectivities observed, we studied the epoxidation of substrates with α-methylene groups containing
Thermal Intramolecular [2+2] Cycloaddition: Synthesis of 3-Azabicyclo[3.1.1]heptanes from Morita-Baylis-Hillman Adduct-Derived 4,4-Diaryl-1,3-dienes
作者:Ko Hoon Kim、Jin Woo Lim、Junseung Lee、Min Jeong Go、Jae Nyoung Kim
DOI:10.1002/adsc.201400571
日期:2014.11.3
AbstractVarious 3‐azabicyclo[3.1.1]heptane derivatives were synthesized from Morita–Baylis–Hillman adduct‐derived 1,3‐dienes bearing a 4,4‐diaryl moiety through a thermal intramolecular [2+2] cycloaddition approach. By using the same approach, bicyclo[3.1.1]heptane, 3‐azabicyclo[3.2.0]heptane, and 3‐oxabicyclo[3.1.1]heptane derivatives could also be synthesized. A structurally similar dimethylallyl derivative underwent an intramolecular ene reaction to afford the pyrrolidine derivative.magnified image