A 12-membered to a strained 11-membered ring: first stereoselective total synthesis of (−)-asteriscunolide C
作者:Rodney A. Fernandes、Vijay P. Chavan
DOI:10.1039/c3cc00316g
日期:——
The first stereoselective total synthesis of (-)-asteriscunolide C has been accomplished in 12 steps in a 16% overall yield. The key step is the conversion of a 12-membered to a strained 11-membered ring with one Z- and two E-double bonds employing a late stage ring-closingmetathesis.
Synthesis of Enantiomerically Pure Eight- and Nine-Membered Lactones by Copper(I) Chloride/2,2’-Bipyridine-Catalyzed Cyclization
作者:Frank O.H. Pirrung、Henk Hiemstra、W. Nico Speckamp、Bernard Kaptein、Hans E. Schoemaker
DOI:10.1055/s-1995-4429
日期:1995.4
The stereocontrolled formation of eight- and nine-membered lactones by Cu(I)Cl/2,2’-bipyridine-catalyzed atom transfer cyclization of enantiomerically pure oxygen-substituted Ï-alkenyl di- and trichloroacetates is described. The lactones are formed exclusively via the endo-cyclization mode and generally show a characteristic cis-relationship between the C-5 and C-6 substituents due to a highly stereoselective ring closure and chlorine transfer.
Dichloromethylenation of Lactones. 6. Efficient Synthesis of Dichloroolefins from Lactones and Acetates Using Triphenylphosphine and Tetrachloromethane
作者:Mohamed Lakhrissi、Yves Chapleur
DOI:10.1021/jo00098a039
日期:1994.9
Triphenylphosphine and tetrachloromethane react cleanly in refluxing tetrahydrofuran with substituted gamma and delta-lactones and some esters to afford the corresponding dichloroolefins in good yields. This new Wittig-type reaction provides an easy entry to this new class of compounds and tolerates a large variety of protecting groups. Application of this methodology to the dichloroolefination of simple lactones, sugar-derived lactones, and other biologically significant lactones is described.
Gruber,W.; Lynen,F., Justus Liebigs Annalen der Chemie, 1962, vol. 659, p. 139 - 156
作者:Gruber,W.、Lynen,F.
DOI:——
日期:——
Chiral synthetic block based on (R)-pantolactone
作者:Fanuza A. Akbutina、Il’ya F. Sadretdinov、Natal’ya K. Selezneva、Mansur S. Miftakhov