Synthesis of [11C]cyanoalkyltriphenylphosphoranes via [11C]cyanide substitution on haloalkylphosphonium salts
作者:Katarina Hörnfeldt、Bengt Långström
DOI:10.1002/jlcr.2580340804
日期:1994.8
were formed in 33–99% radiochemical yield in 5–10 min reaction time. After addition of epichlorohydrin as generator of base, the precursors 1–3 were formed. The potential of the intermediates 1–3 in Witting reactions was shown in model reactions with aromatic and aliphatic aldehydes. The aromatic olefins obtained from 1′–5′ were formed in 85–96 % radiochemical yield, with Z/E ratios between 67/33–75/25
11C 标记的双功能前体 3-[11C] 氰乙基三苯基溴化鏻 (1')、4-[11C] 氰丙基三苯基溴化鏻 (2')、5-[11C] 氰基丁基三苯基溴化鏻 (3')、4-[11C] 的合成提供了氰基丁基三苯基碘化鏻 (4') 和 5-[11C] 氰基丁基三苯基碘化鏻 (5')。在ω-卤代烷基三苯基鏻盐(溴化物或碘化物盐)的取代反应中使用[11C]氰化物引入标记物。鏻盐 1' -5' 在 5-10 分钟的反应时间内以 33-99% 的放射化学产率形成。添加环氧氯丙烷作为碱生成剂后,形成了前体 1-3。在与芳香族和脂肪族醛的模型反应中显示了中间体 1-3 在 Witting 反应中的潜力。从 1'-5' 获得的芳族烯烃的放射化学产率为 85-96%,Z/E 比在 67/33-75/25 之间。脂肪族烯烃以 60-78% 的放射化学产率从 4' 和 5' 处获得。在与 1' 和脂肪醛的反应中,产率下降到