Syntheses of [2.2]metacyclophane-1,9-diene and trans-15,16-dihydropyrene
Syntheses of [2.2]metacyclophane-1,9-diene and trans-15,16-dihydropyrene
复制标题
[2.2]间环芳-1,9-二烯和反式-15,16-二氢芘的合成
DOI：
10.1021/ja00714a071
复制
发表时间：
1970
影响因子：
15
通讯作者：
V. Boekelheide
中科院分区：
文献类型：
--
作者：
R. H. Mitchell;V. Boekelheide
B预期，但乙酸的检出率高达总钴肟的0.01%。为了增加乙酸盐的形成，反应在无水二甲基甲酰胺（DMF）中进行，用1，4_丁烷-二硫醇作为还原剂。在这些更易分解的条件下，观察到50倍的产率增加，提供的乙酸的量高达最初存在的甲基钴肟的1%。在具体的实验中，将1 mmol甲基（吡啶）钴肟溶解在4 ml无水DMF中。在用1atm的CO2置换反应容器中的空气后，加入2 mmol的1，4-丁二硫醇，并将反应混合物在65 ℃下保持12小时。用稀NaOH处理反应溶液时乙酸峰消失，如果反应在氩气下进行，则不存在乙酸峰。也没有观察到乙基-和u-丙基钴肟是否在类似条件下在硫醇存在下用CO2处理（图1）。因此，我们得出结论，类似于方程1的反应可以发生酶促，只要活性位点保持在局部非质子环境中。现有的证据确实表明，一种硫蛋白是CH 3。
B expected, acetic acid was nevertheless detected in yields up to 0.01% of the total cobaloxime. To increase the acetate formation the reaction was conducted in an-hydrous dimethylformamide (DMF) with 1, 4-butane-dithiol as the reducing agent. Under these more favor-able conditions, a 50-fold yield increase was observed, affording acetic acid in amounts of up to 1% of the methylcobaloxime present initially. In a specific experiment 1 mmol of methyl (pyridine) cobaloxime was dissolved in 4 ml of anhydrous DMF. After displacing the air in the reaction vessel by 1 atm of C02, 2 mmol of 1, 4-butanedithiol was added and the reactionmixture was maintained at 65 for 12 hr. Analysis of the liquid phase was performed by glpc using a 5-ft Poropak Q column, as well as a 5-ft 5% FFAP column for separa-tion and comparison with an authentic sample. The acetic acid peak disappears on treating the reaction solution with dilute NaOH and is absent if the reactions are run under argon. It is also not observed if ethyl-and u-propylcobaloximes are treated with C02 in the presence of thiols under similar conditions (Figure 1). We therefore conclude that a reaction analogous to eq 1 could occur enzymatically, provided that the active site is maintained in a locally aprotic environment. The available evidence indeed suggests that a thioprotein is ch3