Journal of Physical Organic Chemistry最新文献_第3页

Torsional influences on cross-conjugated thieno[3,4-b]thiophene photochromes 扭转对交叉共轭噻吩并[3,4-b]噻吩光色团的影响

IF 1.9 4区化学

Journal of Physical Organic Chemistry Pub Date : 2024-08-01 DOI: 10.1002/poc.4650

Nicholas P. Adams, John D. Tovar

引用次数: 0

Theoretical study of atomic electronegativity effects on the excited-state behavior of fluorescent compounds of citrinin 原子电负性对柠檬素荧光化合物激发态行为影响的理论研究

IF 1.9 4区化学

Journal of Physical Organic Chemistry Pub Date : 2024-07-23 DOI: 10.1002/poc.4651

Yue Gao, Meiheng Lv, Zexu Cai, Yuhang Zhang, Tingting Wang, Jianyong Liu, Fangjian Shang, Wenze Li

{"title":"Theoretical study of atomic electronegativity effects on the excited-state behavior of fluorescent compounds of citrinin","authors":"Yue Gao, Meiheng Lv, Zexu Cai, Yuhang Zhang, Tingting Wang, Jianyong Liu, Fangjian Shang, Wenze Li","doi":"10.1002/poc.4651","DOIUrl":"10.1002/poc.4651","url":null,"abstract":"The present work focuses on the light-induced behavior of citrinin derivatives in relation to atomic electronegativity. A detailed theoretical study on the photophysical properties and excited-state behavior of fluorescent compounds of citrinin (Cit-O, Cit-S, and Cit-Se, with different atomic electronegativity) has been conducted, and the effect of electronegativity on the proton transfer in this system has been explained. First, the relevant hydrogen bond parameters and infrared vibrational spectra of the optimized geometrical configurations have been insightfully investigated. It is elucidated that the hydrogen bond is strengthened after photoexcitation, and it provides a driving force for excited-state intramolecular proton transfer (ESIPT). In addition, the frontier molecular orbitals were analyzed, and the intramolecular charge transfer process in all Cit systems, the phenomenon of charge redistribution, facilitates the ESIPT reaction. By constructing potential energy surfaces for different transfer paths, the atomic electronegativity impact on the ESIPT dynamical behavior of the Cit system was determined. This work clarifies the mechanism of the intramolecular proton transfer process in the excited state of citrinin molecules and complements the theoretical study of the atomic electronegativity-regulated citrinin system, which provides a corresponding theoretical basis for the design and synthesis of new luminescence-adjustable citrinin systems.","PeriodicalId":16829,"journal":{"name":"Journal of Physical Organic Chemistry","volume":"37 11","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141774711","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Density functional theory study on frustrated Lewis pairs catalyzed C-H activation of heteroarenes: Mechanism variation tuning by electronic effect 关于受挫路易斯对催化的杂环烯 C-H 活化的密度泛函理论研究：电子效应对机理变化的调整

IF 1.9 4区化学

Journal of Physical Organic Chemistry Pub Date : 2024-07-22 DOI: 10.1002/poc.4652

Youxiang Shao, Kang Xiao, Huize Wang, Yalan Liu

{"title":"Density functional theory study on frustrated Lewis pairs catalyzed C-H activation of heteroarenes: Mechanism variation tuning by electronic effect","authors":"Youxiang Shao, Kang Xiao, Huize Wang, Yalan Liu","doi":"10.1002/poc.4652","DOIUrl":"10.1002/poc.4652","url":null,"abstract":"Unreactive C-H bond activation is a new horizon for frustrated Lewis pairs (FLPs) chemistry. Although concerted mechanism (Science 2015, 349, 513) and stepwise carbene mechanism (Org. Lett. 2018, 20, 1102) have been proposed for the FLPs catalyzed C-H bond activation of 1-methylpyrrole, the influence of electronic properties of FLPs on the reaction mechanism is far away from well-understood. In this study, an assortment of P-B type FLPs with different electronic characteristic was employed to study the catalyzed C-H bond activation of 1-methylpyrrole by using density functional theory calculations. Detailed calculations demonstrated that the reactivity variation and the reaction mechanism binary of FLPs catalyzed C-H activation can be varied by tuning electronic effect of Lewis base center. On the one hand, the concerted C-H activation reactivity is mainly controlled by the electron donation of the lone pair of Lewis base center; thus, the FLPs with electron-donating substituents (FLP1, FLP2, and FLP3) catalyzed the C-H bond activation through concerted mechanism. On the other hand, the reactivity of stepwise carbene mechanism is mostly attributed to the vacant orbital of Lewis acid center; as a result, the FLP5 bearing -P(C6F5)2 preferred to catalyzed the bond activation through concerted mechanism. In contrast, a metathesis mechanism through strained four-membered ring transition state is less feasible. These results should provide deeper insight and broader perspective to understand the structure and function of FLPs for rational design of FLPs catalyzed C-H bond activation.","PeriodicalId":16829,"journal":{"name":"Journal of Physical Organic Chemistry","volume":"37 10","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141774712","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Positive charge delocalization and anti-aromaticity of cations generated by protonation of benzo[a]fluoranthenes in superacid 苯并[a]荧蒽在超酸中质子化产生的阳离子的正电荷分散和反芳香性

IF 1.9 4区化学

Journal of Physical Organic Chemistry Pub Date : 2024-07-14 DOI: 10.1002/poc.4647

Takao Okazaki, Haruki Yamashita, Toshikazu Kitagawa

{"title":"Positive charge delocalization and anti-aromaticity of cations generated by protonation of benzo[a]fluoranthenes in superacid","authors":"Takao Okazaki, Haruki Yamashita, Toshikazu Kitagawa","doi":"10.1002/poc.4647","DOIUrl":"10.1002/poc.4647","url":null,"abstract":"Benzo[a]fluoranthene (4a) is one of non-alternate polycyclic aromatic hydrocarbons. A reaction of 4a in CF3SO3H yielded a dark yellow solution. Direct NMR observation indicated the exclusive formation of carbocation 4aH+ by protonation at the C(8) position. The most deshielded 1H and 13C signals were observed at 8.99 ppm for H(12) and 8.29 ppm for H(1), 182.6 ppm for C(12b), 155.6 ppm for C(8a), and 149.4 ppm for C(7a). The signals for H(4) and H(5) were significantly more shielded than those of 4a. A reaction of 3-tert-butylbenzo[a]fluoranthene (4b) in CF3SO3H afforded carbocation 4bH+ by the protonation at the C(8) position. 4bH+ was gradually converted to 4aH+. The changes in 13C NMR chemical shifts (Δδ13C) suggested that positive charge was delocalized into mainly seven carbons in 4aH+ and 4bH+. The observed cations were found to be the most stable cations among the possible protonation cations by the DFT method. The NICS(1)zz values for the five-membered rings were calculated to be 35.6 for 4aH+ and 34.4 for 4bH+ by GIAO-B3LYP/6-311+G(2d,p). The experimental NMR and the NICS(1)zz data indicated that the five-membered rings in 4aH+ and 4bH+ exhibited anti-aromaticity.","PeriodicalId":16829,"journal":{"name":"Journal of Physical Organic Chemistry","volume":"37 10","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141650513","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Influence of halogen substituents on sensitivity towards detonation of polycyclic nitroaromatic high-energy molecules 卤素取代基对多环硝基芳香族高能分子引爆敏感性的影响

IF 1.9 4区化学

Journal of Physical Organic Chemistry Pub Date : 2024-07-12 DOI: 10.1002/poc.4649

Ivana S. Veljković, Aleksandra B. Đunović, Dušan Ž. Veljković

引用次数: 0

Exploring the specific chemistries of the cycloaddition reactions of 5-benzoyl-3(2H)-isothiazolone and stable nitrile oxides: Insights from Density Functional Theory analysis 探索 5-苯甲酰基-3(2H)-异噻唑酮和稳定腈氧化物环化反应的特殊化学性质：密度泛函理论分析的启示

IF 1.9 4区化学

Journal of Physical Organic Chemistry Pub Date : 2024-07-11 DOI: 10.1002/poc.4645

Muntaka Is-mail, Albert Aniagyei, Caroline R. Kwawu, Gabriel Amankwah, Elliot Menkah, Evans Adei

{"title":"Exploring the specific chemistries of the cycloaddition reactions of 5-benzoyl-3(2H)-isothiazolone and stable nitrile oxides: Insights from Density Functional Theory analysis","authors":"Muntaka Is-mail, Albert Aniagyei, Caroline R. Kwawu, Gabriel Amankwah, Elliot Menkah, Evans Adei","doi":"10.1002/poc.4645","DOIUrl":"10.1002/poc.4645","url":null,"abstract":"Isothiazolones are important heterocyclics with pharmacological potency such as anti-inflammatory, anticancer, antimicrobial, and robust biocidal (used in agrochemicals). This study seeks to provide mechanistic insight into the chemo- and regio-selectivities of the [3 + 2] cycloaddition reaction of 5-benzoyl-3(2H)-isothiazolone (A1) with two stable nitrile oxides, that is, mesitonitrile oxide (A2) and dichlorobenzonitrile oxide (A3) using M06-2X hybrid density functional calculations coupled with the 6-311G (d, p) basis sets. Mesitonitrile oxide A2 chemo-selectively adds across the carbonyl of the benzyl group of A1 while dichloro benzonitrile oxide A3 preferentially adds across the ethylene center of A1. Derivatization of A1 with electron-donating groups lowers the activation barriers by a very minute margin ranging from 0.1 to 0.5 kcal/mol whereas electron-withdrawing groups significantly decrease the energetics of the reaction by a margin of 1.1 to 2.5 kcal/mol. Solvation with chloroform does not affect the selectivity of the reaction but tends to increase both activation and reaction energies of the various routes. Analysis of the Parr function on different reactive sites of A1 shows the addition of A2 via the atomic center with the largest Mullikan atomic spin densities. Substitution of the S-heteroatom with C, O, or N does not affect the regioselectivity of the reaction but lowers the activation energies in the reaction of A1 with A3. The global electron density transfer (GEDT) values predict a polar reaction between A1 and A2 whereas the reaction of A1 and A3 is non-polar.","PeriodicalId":16829,"journal":{"name":"Journal of Physical Organic Chemistry","volume":"37 10","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141614088","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Exploring regioselectivity in 1,3-dipolar cycloaddition of thioamides, selenoamides, and amides with propadienyl cation derivatives using density functional theory 利用密度泛函理论探索硫代酰胺、硒代酰胺和酰胺与丙二烯阳离子衍生物进行 1,3 双极环加成时的区域选择性

IF 1.9 4区化学

Journal of Physical Organic Chemistry Pub Date : 2024-07-04 DOI: 10.1002/poc.4646

Vanishree Shankar Naik, Ganga Periyasamy

{"title":"Exploring regioselectivity in 1,3-dipolar cycloaddition of thioamides, selenoamides, and amides with propadienyl cation derivatives using density functional theory","authors":"Vanishree Shankar Naik, Ganga Periyasamy","doi":"10.1002/poc.4646","DOIUrl":"10.1002/poc.4646","url":null,"abstract":"This study explores the potential mechanisms (Paths 1 and 2) involved in the regioselective dipolar cycloaddition of thioamides, selenoamides, and amides with propargyl alcohol using density functional theory (DFT). Our calculations reveal that the initial step involves the formation of a cation with catalyst. Subsequently, isomerization occurs between cations I and II via 1,3-hydride transfer in the second step. We analyzed the global reactivity index and frontier molecular orbital (FMO) theory to gain insights into the mechanism. In the third step, chalcoamides attack cations I and II, forming an intermediate. The formation of a five-member ring intermediate constitutes the fourth step, followed by hydrogen transfer to produce stable five-member heterazole compounds in the final step. We demonstrated the influence of substituents in the electrophile by employing various electron-withdrawing and donating groups. Additionally, we examined the effect of the dielectric medium on the reaction barrier using polarizable continuum model. Thus, this study provides valuable insights for the rational design of more efficient 1,3-dipolar cycloaddition reactions yielding regioselective products.","PeriodicalId":16829,"journal":{"name":"Journal of Physical Organic Chemistry","volume":"37 10","pages":""},"PeriodicalIF":1.9,"publicationDate":"2024-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141575182","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Paddlanes revisited: Which are the smallest possible? 重新审视 Paddlanes：哪些是最小的？

IF 1.9 4区化学

Journal of Physical Organic Chemistry Pub Date : 2024-07-01 DOI: 10.1002/poc.4644

Gary W. Breton

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Special issue devoted to the 15th Latin American Conference on Physical Organic Chemistry (CLAFQO-15) 第 15 届拉丁美洲物理有机化学会议（CLAFQO-15）特刊

IF 1.9 4区化学

Journal of Physical Organic Chemistry Pub Date : 2024-06-14 DOI: 10.1002/poc.4643

Vanderlei Gageiro Machado