24871-12-3Relevant articles and documents
Intramolecular Reductive Cyclization of Unsaturated Keto- or Aldo-esters by Samarium(II) Di-iodide: A Ready Synthesis of Bicyclic g-Lactones
Fukuzawa, Shin-ichi,Iida, Masahiro,Nakanishi, Akira,Fujinami, Tatsuo,Sakai, Shizuyoshi
, p. 920 - 921 (1987)
Treatment of unsaturated keto- or aldo-esters with SmI2 in tetrahydrofuran (THF) or THF-hexamethylphoshoramide affords bicyclic γ-lactones in moderate to good yields.
(HMe 2 SiCH 2) 2: A Useful Reagent for B(C 6 F 5) 3 -Catalyzed Reduction-Lactonization of Keto Acids: Concise Syntheses of (-)- cis -Whisky and (-)- cis -Cognac Lactones
Xie, Hengmu,Lu, Ji,Gui, Yingying,Gao, Lu,Song, Zhenlei
supporting information, p. 2453 - 2459 (2017/10/06)
(HMe 2 SiCH 2) 2 has been utilized as a useful reagent for B(C 6 F 5) 3 -catalyzed reduction-lactonization of keto acids to synthesize γ- and δ-lactones. The process led concisely to (-)- cis -whisky and (-)- cis -cognac lactones in respective overall yields of 32% and 36%.
On the stereochemical course of the addition of allylsilanes to aldehydes
Denmark, Scott E.,Weber, Eric J.,Almstead, Neil G.,Wolf, Larry M.
experimental part, p. 7701 - 7718 (2012/09/11)
Model compounds 3 and 5 have been studied to determine the orientation of the reacting double bonds in the transition state of the allylmetal-aldehyde addition. These models were designed to remove any intrinsic steric bias for the formation of the bicyclic products that would obfuscate a stereoelectronic contribution to the transition states. Model system 3 revealed a modest preference for the synclinal transition state, albeit in very low yields. Model system 5 underwent selective and largely Lewis acid independent cyclization primarily via a synclinal transition state. The high proximal selectivity observed in these cyclizations likely reflects the selectivity of an unhindered allylmetal-aldehyde addition for the synclinal transition state and results from a stereoelectronic preference, not an intrinsic steric bias, for the synclinal arrangement of double bonds.
