CONVENIENT GENERAL-METHOD FOR THE PREPARATION OF PRIMARY ALKYLLITHIUMS BY LITHIUM IODINE EXCHANGE
CONVENIENT GENERAL-METHOD FOR THE PREPARATION OF PRIMARY ALKYLLITHIUMS BY LITHIUM IODINE EXCHANGE
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DOI：
10.1021/jo00306a021
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发表时间：
1990-09-14
影响因子：
3.6
通讯作者：
PUNZALAN, ER
中科院分区：
文献类型：
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作者：
BAILEY, WF;PUNZALAN, ER
有机卤化物和有机锂之间的复分解反应被称为锂-卤素交换，大约50年前由维蒂希和吉尔曼的小组发现。1，2该反应是一种产生有利于更稳定的有机锂的平衡混合物的可逆过程，3已被广泛用于制备相对稳定的有机金属化合物，如芳基-、4 ′ 10乙烯基-5-、9 ′ 11、12和环丙基锂6 ′ 9、13，其方法是用反应性更高的烷基锂处理相应的有机卤化物，但是除了少数显著的例外，使用该交换物来产生烷基锂的成功率较低。4 - 9在通过锂-卤素交换形成简单烷基锂中通常遇到的困难是反应的可逆性质和当用有机锂处理时烷基卤化物的反复无常行为的结果。竞争反应，如α-消除，4 '9 α-金属化，17和Wurtz型偶联生产对称和混合烃3，6”9可以严重损害交换作为一个有效的途径烷基锂。最近（1）（a）Wittig，G.; Pockels，U.;德罗日Ber. Chem. 1938年71年1903年(b)Gilman，H.; Langham，W.; Alberby，A. LJ Am. 1939，61，106.
The metathesis between an organic halide and an or-ganolithium known as the lithium-halogen interchange was discovered some 50 years ago by the groups of Wittig and Gilman. 1, 2 The reaction, which is a reversible process leading to an equilibrium mixture favoring the more stable organolithium, 3 has been used extensively to prepare relatively stable organometallics such as aryl-, 4'10 vinyl-5-9, 11, 12 ancj cyclopropyllithiums6" 9, 13 by treatment of the corresponding organohalide with a more reactive alkyl-lithium, but the use of the interchange for the generation of an alkyllithium has, with a few notable exceptions, 14" 16 met with less success. 4" 9 The difficulties commonly en-countered in the formation of simple alkyllithiums by lithium-halogen interchange are a consequence of the re-versible nature of the reaction and the capricious behavior of alkyl halides when treated with an organolithium. Competing reactions such as ß-elimination, 4'9 a-metala-tion, 17 and Wurtz-type coupling to producesymmetrical and mixed hydrocarbons3, 6" 9 can seriously compromise the interchange as an efficient route to alkyllithiums. Recent (1)(a) Wittig, G.; Pockels, U.; Droge, H. Chem. Ber. 1938, 71, 1903.(b) Gilman, H.; Langham, W.; Jacoby, A. LJ Am. Chem. Soc. 1939, 61, 106.