CHELATION AS A DRIVING FORCE IN ORGANIC REACTIONS .4 SYNTHESIS OF ALPHA-NITRO ACIDS BY CONTROL OF CARBOXYLATION-DECARBOXYLATION EQUILIBRIUM
CHELATION AS A DRIVING FORCE IN ORGANIC REACTIONS .4 SYNTHESIS OF ALPHA-NITRO ACIDS BY CONTROL OF CARBOXYLATION-DECARBOXYLATION EQUILIBRIUM
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DOI：
10.1021/ja00888a031
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发表时间：
1963-01-01
影响因子：
15
通讯作者：
STILES, M
中科院分区：
文献类型：
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作者：
FINKBEINER, HL;STILES, M
用二氧化碳和甲氧镁(甲基碳酸镁)处理初级硝基石蜡，得到相应的硝基羧酸镁盐。这些盐可以很容易地转化为游离硝酸、酯或相应的氨基酸。因此，羧化反应是合成这些化合物的一种有价值的方法。根据硝酸根与甲醇钠和甲氧基镁的对比行为，得出结论：羧化反应的成功取决于镁离子与硝酸乙酯双阴离子的络合作用。本文报道了硝酸根在水中的第一和第二电离常数。碳链的长度改变一个单位通常涉及二氧化碳的增加或损失。只有在羧化反应中使用最强的亲核剂，如格氏试剂，并在脱羧基反应中进行非常剧烈的热解处理，才能合成并降解简单的羧酸。在制备化学和生物化学中更有趣的是那些双功能酸，如I(等式)。1)其中X可以是酰基、羧基、硝基、氰基、
Treatment of primary nitroparaffinswith carbon dioxide and magnesium methoxide (magnesium methyl car-bonate) leads to magnesium salts of the corresponding-nitrocarboxylic acids. These salts can be converted easily into the free nitro acids, the esters or the corresponding amino acids. The carboxylation reaction thus serves as a valuable method for synthesizing these compounds. On the basis of thecontrasting behavior of nitroacetic acid toward sodium methoxide and magnesium methoxide, it is concluded that the success of the car-boxylation reaction rests upon chelation of magnesium ions with the nitroacetate dianion. Thefirst and second ionization constants of nitroacetic acid in water are reported.Alteration of the length of a carbon chain by one unit often involves the addition or loss of carbon dioxide. Simple carboxylic acids can be synthesized and degraded by this scheme only if the strongest nucleophiles, such as Grignard reagents, are used in the carboxylation, and very drastic pyrolytic treatment in the decarboxylation. More interesting in preparative chemistry and biochemistry4 are those bifunctional acids such as I (eq. 1) where Xmay be acyl, carboxyl, nitro, cyano,