Convergent synthesis of polycyclic ethers via the intramolecular allylation of alpha-acetoxy ethers and subsequent ring-closing metathesis.
The Lewis acid mediated reaction of alpha-acetoxy ethers 15-22 gave the corresponding cyclized products 23, 25, 27, 29, 31, 32, 34, and 36 in good yields with high stereoselectivities. Those cyclized products were subjected to ring-closing metathesis to afford the polycyclic ethers 38-42, 44, and 45 in good yields. The usefulness of the present methodology was demonstrated by the convergent synthesis of the CDEF ring system of brevetoxin B (1) and the CDEFG ring system of gambierol (2).
Kadota
Isao
I
Research Center for Sustainable Materials Engineering, Institute of Multidisciplinary Research for Advanced Materials, and Department of Chemistry, Graduate School of Science, Tohoku University, Sendai 980-8578, Japan.
Ohno
Akio
A
Matsuda
Kumiko
K
Yamamoto
Yoshinori
Y
D000498:Allyl Compounds / Q000737:chemistry; D002922:Ciguatoxins; D004988:Ethers, Cyclic / Q000138:chemical synthesis*; D011083:Polycyclic Compounds / Q000138:chemical synthesis*; D035964:Oxocins
D000498:Allyl Compounds; D002922:Ciguatoxins; D004988:Ethers, Cyclic; D011083:Polycyclic Compounds; C435770:gambierol; D035964:Oxocins