Pyrrole-Modified Subporphyrins Bearing a Sulfur-Containing Heterocyclic Unit
Pyrrole-Modified Subporphyrins Bearing a Sulfur-Containing Heterocyclic Unit
复制标题
带有含硫杂环单元的吡咯改性亚卟啉
DOI：
10.1002/hlca.201800025
复制
发表时间：
2018
影响因子：
1.8
通讯作者：
Osuka Atsuhiro
中科院分区：
文献类型：
--
作者：
Yoshida Kota;Osuka Atsuhiro
以α-氟代次氯膦2为原料，经Cu（NO3）2的选择性硝化，再与3-巯基丙酸甲酯进行双SN 2反应，合成了含硫杂环结构的吡咯修饰亚卟啉（PMSubPs），即二噻唑亚卟啉5、二噻嗪亚二氯啉6和氧代二噻嗪亚二氯啉7.在钨催化剂存在下，H2 O2氧化5得到S，S-二氧代二噻唑亚卟啉8，Cu（NO3）2·3 H2O硝化5得到β-硝基二噻唑亚卟啉9或β，β-二硝基二噻唑亚卟啉10a和10 b。在固态下，8和9中的二噻唑单元几乎是平面的，但6中的二噻嗪单元和7中的2-氧代二噻嗪单元是非平面的。与亚氯芬相比，二硫唑亚卟啉5具有显著降低的向阻环电流和极大扰动的吸收光谱，在501和660 nm处显示出大量分裂的类Q带。5的这些电子和光学性质在6和7中明显减弱，在8中完全消失，表明二硫键对大扰动的重要性。
As new pyrrole‐modified subporphyrins (PMSubPs) bearing a sulfur‐containing heterocyclic unit, dithiazolosubporphyrin5, dithiazinosubchlorin6, and oxodithiazinosubchlorin7were synthesized fromα‐fluorosubchlorophin2via α’‐selective nitration with Cu(NO3)2followed by double SN2 reaction with methyl 3‐mercaptopropionate as a key step. Oxidation of5with H2O2in the presence of a tungsten catalyst affordedS,S‐dioxodithiazolosubporphyrin8and nitration of5with Cu(NO3)2·3H2O gaveβ‐nitrodithiazolosubporphyrin9orβ,β‐dinitrodithiazolosubporphyrins10aand10bdepending on reaction conditions. In the solid‐states, the dithiazole units in8and9are almost planar but the dithiazine unit in6and the 2‐oxodithiazine unit in7are non‐planar. Compared to subchlorophin1, dithiazolosubporphyrin5possesses a significantly reduced diatropic ring current and a greatly perturbed absorption spectrum showing largely split Q‐like bands at 501 and 660 nm. These perturbed electronic and optical properties of5are considerably attenuated in6and7and completely vanished in8, suggesting the importance of disulfide bond for the large perturbation.