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英语翻译The reaction of 23 with 1,2,4,5-tetraiodobenzene inpiper

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英语翻译
The reaction of 23 with 1,2,4,5-tetraiodobenzene in
piperidine under copper-free Pd(0) catalysis to produce
1,2,4,5-tetra((3-(4-pyridyl)ethynyl)bicyclo[1.1.1]pent-1-ylethynyl)
benzene (6) (Scheme 3) was significantly slower
than the analogous reaction with 1,3,5-triiodobenzene.
Because of the five possible intermediates on the way to
the tetrasubstituted product,the probability of side
reactions and the possible number of unwanted byproducts
were much larger.The reaction proceeded in a stepwise fashion,and the anticipated intermediates gave
rise to very complicated 1H NMR patterns that ultimately
coalesced into a single aryl proton peak.The reaction took
up to 10 days to run to completion,and the addition of
catalyst in regular intervals was necessary.The regulation
of the temperature between 45 and 50 °C was
extremely critical since below that temperature range,
no reaction took place,while above it,the reduction of
the aryl iodide became a major side reaction.
23日的反应1,2,4,5 - tetraiodobenzene在
哌啶铜下无钯( 0 )催化产生
1,2,4,5 -四( ( 3 - ( 4 -吡啶基)乙炔)双环[ 1.1.1 ]压抑- 1 - ylethynyl )
苯( 6 ) (计划3 )显着放缓
比类似的反应1,3,5 triiodobenzene .
由于五种可能的中间道路上的
产品的tetrasubstituted的概率方
反应和尽可能多的有害副产品
人大得多.反应过程中的一个循序渐进的方式,以及预计中间体了
上升到非常复杂的1H NMR模式,最终
合并成一个单一芳质子高峰.反应了
长达10天完成运行,并增加
催化剂在定期间隔是必要的.该条例
温度45至50 ℃是
极为重要,因为低于这个温度范围内,
没有反应发生,而它上面,减少
在芳基碘成为一个主要的不良反应.