Formation of 8-RS-BODIPYs via direct substitution of 8-MeS-BODIPY by RSH (R = Et, Pr, Bu, t Bu, n -C 12 H 25 , C 6 H 5 , p -MeC 6 H 4 , p -MeOC 6 H 4 , and 2,6-Me 2 C 6 H 3 )
2015; NRC Research Press; Volume: 94; Issue: 3 Linguagem: Inglês
10.1139/cjc-2015-0303
ISSN1480-3291
AutoresRobinson I. Roacho, Alejandro J. Metta‐Magaña, José L. Belmonte‐Vázquez, Eduardo Peña‐Cabrera, Keith H. Pannell,
Tópico(s)Molecular Sensors and Ion Detection
ResumoReactions between 8-RS-BODIPY (R = Me, 1) and alkyl and aryl thiols were readily accomplished in dichloromethane to provide a synthetic pathway to a range of new 8-organothio-BODIPYs in good yield. The new alkyl 8-RS-BODIPYs (R = Et, 2; Pr, 3; Bu, 4; t Bu, 5; n-dodecyl, 6) exhibit absorption and emission properties essentially unchanged from those of 1 whereas the arylthio analogs (R = Ph, 7; 2,6-Me 2 C 6 H 3 , 8; p-MeC 6 H 4 , 9; p-MeOC 6 H 4 , 10) exhibit no fluorescence with the exception of 7, and then only in hexane. In common with other related 8-substituted BODIPYs, the new 8-alkylthio-BODIPY dyes show decreasing fluorescence intensity as solvent polarity increases. Compounds 2, 3, 7, and 8 were characterized via single-crystal X-ray analysis; the alkyl derivatives 2 and 3 exhibited planar BODIPY cores with co-planar organothio- substituents whereas the aryl derivatives exhibited both BODIPY core deformation and significant twisting about the S–C (8) bond removing co-planarity between the aryl group and the distorted BODIPY core. These deformations coincide with the significantly reduced emission properties.
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