Metal-Catalyzed Cyclization of β- and γ-Allenols Derived from D-Glyceraldehyde-Synthesis of Enantiopure Dihydropyrans and Tetrahydrooxepines: An Experimental and Theoretical Study
作者:Benito Alcaide、Pedro Almendros、Teresa Martínez del Campo、Elena Soriano、José L. Marco-Contelles
DOI:10.1002/chem.200901180
日期:2009.9.14
Regiocontrolled metal‐catalyzed preparations of enantiopuredihydropyrans and tetrahydrooxepines have been synthesized starting from β‐ and γ‐allenols derivedfrom D‐glyceraldehyde. The PdII‐catalyzed cyclizative coupling reactions of β‐allenols 1 a and 1 b with allyl bromide effectively afforded enantiopure tetrafunctionalized dihydropyrans through a 6‐endo oxycyclization protocol, whereas the gold‐
Controlled Heterocyclization/Cross-Coupling Domino Reaction of β,γ-Allendiols and α-Allenic Esters: Method and Mechanistic Insight for the Preparation of Functionalized Buta-1,3-dienyl Dihydropyrans
作者:Benito Alcaide、Pedro Almendros、Teresa Martínez del Campo、M. Teresa Quirós、Elena Soriano、José L. Marco-Contelles
DOI:10.1002/chem.201300774
日期:2013.10.11
Starting from β,γ‐allendiols and α‐allenic acetates, a chemo‐ and regiocontrolled palladium‐catalyzed methodology has provided access to enantiopure 3,6‐dihydropyrans that bear a buta‐1,3‐dienyl moiety. Thus, it has been demonstrated for the first time that the preparation of six‐membered heterocycles through cross‐coupling reactions of two different allenes can be accomplished. These heterocycliz