Photocyclization Reactions of Epoxy Nitriles via Carbonyl Ylides. Formation of Spiroketals, Spiroethers, and a Spirolactone.
作者:Masashi KOTERA、Keitaro ISHII、Masanori SAKAMOTO
DOI:10.1248/cpb.43.1621
日期:——
Photocyclization reactions (γ=254nm) of γ-methyl δ-(4-hydroxybutyl) and δ-(-4-hydroxypentyl) α, β-unsaturated γ, δ-epoxy nitriles gave spiroketals and spirothers diastereoselectively, whereas reaction of δ-(6-hydroxyhexyl) nitrile allorded no cyclization product. In addition, photocyclization of nitrile bearing a carboxyl group in the δ-side-chain afforded spirolactone.
γ-甲基δ-(4-羟基丁基)和δ-(-4-羟基戊基)α, β-不饱和γ, δ-环氧腈的光环化反应(γ=254nm)选择性地生成了螺酮和螺醚,而δ-(6-羟基己基)腈的反应则没有产生环化产物。此外,含有羧基的腈在δ侧链的光环化反应生成了螺内酯。