Near-infrared dyes and fluorophores based on diketopyrrolopyrroles
Near-infrared dyes and fluorophores based on diketopyrrolopyrroles
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DOI：
10.1002/anie.200604763
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发表时间：
2007-01-01
影响因子：
16.6
通讯作者：
Daltrozzo, Ewald
中科院分区：
文献类型：
--
作者：
Fischer, Georg M.;Ehlers, Andreas R.;Daltrozzo, Ewald
在过去的几十年里，我们的研究活动一直关注分子结构和荧光之间的相关性。[1，2]这项研究的一个中心主题是近红外(NIR)染料的合成和光谱研究[3]，以深入了解可获得的荧光量子产率[4，5]在多大程度上受到S0$S1能隙的限制。[6，7]我们关于1，4-二氮杂二酮与杂芳基乙腈在POCl3中缩合的结果[8]促使我们与二酮基吡咯(DPPs)1进行反应。[9]本文报告了研究结果试图用POCl3激活DPP的羰基，然后将中间体与亲核试剂转化，只会导致单取代或开环。根据方案1，1和2在甲苯中与过量的POCl3反应生成双取代近红外染料3。通过记录吸收光谱并在DPP用完和/或出现吸收短波长的产物时立即停止加热来控制反应进程。用丙酮消化产物，然后用闪蒸层析法(硅胶/CHCl3或CH2Cl2)进行纯化。近红外染料3a-3h(3b-3h的结构和光谱数据可在支持信息中找到)是由1[11]和2按此程序(方案1)合成的。反应过程在所有情况下都是相同的，并观察到在350 nm以下有强吸收的副产物。这些副产物最有可能是由DPPS戊二烯环系打开形成的化合物。
Our research activities over the last few decades have concerned correlations between molecular structure and fluorescence.[1, 2] A central theme of the research has been the synthesis and spectroscopic investigations of near-infrared (NIR) dyes [3] to get insights into what degree the obtainable fluorescence quantum yields [4, 5] are restricted by the S0 $ S1 energy gap.[6, 7] Our results [8] on the condensation of 1, 4-phthalazinediones with heteroarylacetonitriles in POCl3 prompted us to carry out the reaction with diketopyrrolopyrroles (DPPs) 1.[9] Herein we report the results of the investigations.To date, attempts to activate the carbonyl group of DPPs with POCl3, and to subsequently convert the intermediates with nucleophiles, only led to monosubstitution or to ring opening.[9, 10] The reaction of 1 and 2 in refluxing toluene with an excess of POCl3 according to Scheme 1 afforded disubstituted NIR dyes 3. The progress of the reaction was controlled by recording absorption spectra and stopping the heating as soon as the DPP was used up and/or products absorbing at short wavelengths appeared. Purification was carried out by digesting the product in acetone and subsequent flash chromatography (silica gel/CHCl3 or CH2Cl2). The NIR dyes 3a–3h (the structures and spectroscopic data of 3b–3h can be found in the Supporting Information) were synthesized according to this procedure (Scheme1) from the reaction of 1 [11] and 2. The course of the reactions was the same in all cases and side-products with strong absorptions below 350 nm were observed. These side-products are most likely compounds formed by the opening of the DPPs pentalene ring system.