After-effects of lithium-mediated alumination of 3-iodoanisole: isolation of molecular salt elimination and trapped-benzyne products
作者:Elaine Crosbie、Alan R. Kennedy、Robert E. Mulvey、Stuart D. Robertson
DOI:10.1039/c2dt11893a
日期:——
Gaining a deeper understanding of the modus operandi of heterometallic lithium aluminate bases towards deprotonative metallation of substituted aromatic substrates, we have studied the reactions and their aftermath between our recently developed bis-amido base ‘iBu2Al(μ-TMP)2Li’ 3 and 3-halogenated anisoles. Ortho-metallation of 3-iodoanisole with 3 results in a delicately poised heterometallic intermediate
为了更深入地了解异金属铝酸锂碱对取代的芳族底物进行去质子化金属化的操作方式,我们研究了我们最近开发的双酰胺基“ i Bu 2 Al(μ-TMP)2 Li”之间的反应及其后果。3和3卤代异氰酸酯。的正金属化3-碘苯甲醚用3生成精细平衡的杂金属中间体,将其分解为同金属物种,然后苯并 即使在低温下或在非极性溶剂中也无法抑制(正己烷)。分离了均金属成分[LiI·TMP(H)] 4(5)和i Bu 2 Al(TMP)·THF(6),而反应性苯炔中间体已通过Diels–Alder环化反应被捕集,1,3-二苯基异苯并呋喃产生1-甲氧基-9-10-二苯基-9-10-环氧蒽(7)。在极性THF溶液中,LiTMP跨苯炔官能团的亲核加成,然后用碘进行亲电淬灭,生成三取代的芳香族物质1-(2-碘-3-甲氧基苯基)-2,2,6,6-四甲基哌啶(8)。化合物5-8的特征是固态的单晶X射线衍射和溶液中的多核NMR光谱。