Mechanism of 3‘,5‘-Dimethoxybenzoin Ester Photochemistry: Heterolytic Cleavage Intramolecularly Assisted by the Dimethoxybenzene Ring Is the Primary Photochemical Step
Modulated photochemical reactivities of O-acetylated (3’,5’-dimethoxyphenyl)heteroaryl acyloin derivatives under direct irradiation and photo-induced electron transfer conditions
part of the O-acetylated cross-acyloin derivatives. The furan, thiophene and bithiophene derivatives led to the expected cyclized (benzofuran capped) products but the derivatives with extended conjugation decomposed under direct irradiation. However, under irradiation in the presence of an electron donor such as triethylamine, the extended acyloin derivatives afforded both cyclized and deacetoxylated
3′,5′-二甲氧基苯偶姻酯是重要的可光除去的保护基,其在光释放时形成2-苯基苯并呋喃衍生物。我们利用相似的概念来测试通过直接光照射和光诱导的电子转移反应使O-乙酰化的(3',5'-二甲基苯基)杂芳基酰基蛋氨酸衍生物经受将苯并呋喃部分安装到共轭骨架上的光化学方法。对这些光化学方法进行了探索,以发现附着在O酮部分上的各种杂芳族底物-乙酰化的交叉酰基辅酶衍生物。呋喃,噻吩和联噻吩衍生物可产生预期的环化(苯并呋喃封端)产品,但在直接辐射下具有扩展共轭作用的衍生物会分解。然而,在电子给体例如三乙胺存在下的辐射下,扩展的酰基辅酶衍生物既提供环化的产物又提供脱乙酰氧基化的产物。对于溶液处理的有机场效应晶体管,还探索并测试了扩展的环化产物的半导体性质,该晶体管的最大空穴迁移率为1.3×10 -6 cm 2 V -1 s -1。
Photoinduced Release of a Chemical Fuel for Acid–Base‐Operated Molecular Machines
作者:Chiara Biagini、Flaminia Di Pietri、Luigi Mandolini、Osvaldo Lanzalunga、Stefano Di Stefano
DOI:10.1002/chem.201800474
日期:2018.7.17
forth motions of the acid–base‐operated molecularswitch 1 are photo‐controlled by irradiation of a solution, which also contains the photolabile pre‐fuel 4. The photo‐stimulated deprotection of the pre‐fuel produces controlled amounts of acid 2, the base‐promoted decarboxylation of which fuels the back and forth motions of the Sauvage‐type [2]‐catenane‐based molecularswitch. Because switch 1 and
Synthesis and properties of carbamoyl derivatives of photolabile benzoins
作者:George Papageorgiou、John E.T. Corrie
DOI:10.1016/s0040-4020(97)00009-4
日期:1997.3
Carbamoyl derivatives of photolabile benzoins, particularly of 3′,5′-dimethoxybenzoin, are readily prepared via the mixed p-nitrophenyl carbonate of the benzoin. The method is most suitable for secondary amines, since many primary amines exist in varying proportions as the cyclic hydroxyoxazolidinone tautomer. In alkaline solution (0.2 M NaOH) the carbamates of unsymmetrical benzoins are readily equilibrated
光不稳定的安息香,特别是3',5'-二甲氧基安息香的氨基甲酰基衍生物可以通过安息香的混合对硝基苯基碳酸酯容易地制备。该方法最适合于仲胺,因为许多伯胺以不同的比例作为环状羟基恶唑烷酮互变异构体存在。在碱性溶液(0.2 M NaOH)中,不对称安息香的氨基甲酸酯很容易达到平衡。3',5'-二甲氧基苯偶姻氨基甲酸酯的快速光解会在快速杂解过程中生成氨基甲酸酯阴离子,胺的释放受脱羧速率的控制。
Improved polyaromatic benzoin photoremovable protecting groups
作者:Laura J. McKay、Carl-Johan Carling、Neil R. Branda
DOI:10.1016/j.jphotochem.2021.113530
日期:2021.12
Two novel photoremovable protecting groups in the benzoin class have been prepared and their photochemistry investigated. These polyaromatic benzoin photoremovable protecting groups have significantly improved molar extinction coefficients with absorptions that extend further towards the visible region of the spectrum and should not be hindered by a ‘inner filter’ effects, making them appealing for
New photolabile amino protecting groups: photogeneration of amines from [(3′,5′-dimethoxybenzoinyl)oxy]carbonyl carbamates
作者:James F. Cameron、C. Grant Willson、Jean M. J. Fréchet
DOI:10.1039/c39950000923
日期:——
A novel class of photoiabile amino protecting groups, based on [(3â²,5â²-dimethoxybenzoinyl)oxy]carbonyl groups, is presented and their scope and versatility demonstrated by the photogeneration of free primary and secondary amines.