CHEMISTRY OF ALIPHATIC DISULFIDES .3. FORMATION OF SULFIDES DURING CLEAVAGE BY CYANIDE ION
CHEMISTRY OF ALIPHATIC DISULFIDES .3. FORMATION OF SULFIDES DURING CLEAVAGE BY CYANIDE ION
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DOI：
10.1021/ja01483a034
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发表时间：
1961-01-01
影响因子：
15
通讯作者：
CARROLL, FI
中科院分区：
文献类型：
--
作者：
HISKEY, RG;CARROLL, FI
三种不对称二硫化物的氰离子裂解主要生成不对称硫化物，此外还有少量的硫氰酸盐和捕获的硫醇。更稳定的硫醇优先生成。硫化物的形成是硫醇和硫氰酸盐之间的二次反应的结果，硫氰酸盐是在最初的裂解中形成的。为反应的平衡性质提供了证据。几种不对称脂肪族二硫化物的氰离子裂解方向与生成的硫醇离子的稳定性有关：阴离子稳定性较大的硫醇和相应的烷基硫氰酸盐占主导地位。为了对这一建议进行更彻底的测试，需要6·6个底物，其潜在的稳定性等于或大于先前使用的碳甲基-D-硫醇钠(I)。因此，甲基6-酮-3，4-二硫杂环己烷。用上述一般条件裂解了4-苯基-3，4-二硫代丁酸甲酯(II)、4-苯基-3，4-二硫代丁酸甲酯(III)、1.28和5-(4-硝基苯基)-3，4-二硫戊酸甲酯(IV)。
Cyanide ion cleavage of three unsymmetrical disulfides yield unsymmetrical sulfides as the major product and, in addition, small amounts of thiocyanates and trapped mercaptides. The more stable mercaptide is preferentially produced. Formation of sulfide occurs as the result of a secondary reaction between mercaptide and thiocyanate formed in the initial cleavage. Evidence is presented for the equilibrium nature of the reaction. Possible mechanisms are discussed.The direction of cyanide ion cleavage of several unsymmetrical aliphatic disulfides has been found1 to be related to the stability of the mercaptide ion produced: the mercaptide of greater anionic stability and the corresponding alkyl thiocyanate predominate. In order to provide a more thorough test of this proposal, 6· 6 substrates containing a potential mercaptide of stability equal to or greater than the previously used sodium carbo-metboxymeth; d mercaptide (I) were desirable. Thus methyl 6-keto-3, 4-dithiahept. anoate (II),“ApKa" 0.06, 7 methyl 4-phenyl-3, 4-dithiabutanoate (III),“ApKa” 1.28, and methyl 5-(4-nitrophenyl)-3, 4-dithiapentanoate (IV) were cleaved using the general conditionspreviously described. 1 The re-