TY - JOUR
T1 - Fluoride-Triggered Ring-Opening of Photochromic Diarylpyrans into Merocyanine Dyes
T2 - Naked-Eye Sensing in Subppm Levels
AU - Mukhopadhyay, Arindam
AU - Maka, Vijay Kumar
AU - Moorthy, Jarugu Narasimha
N1 - Funding Information:
J.N.M. is thankful to the Science and Engineering Research Board (SERB), New Delhi, for financial support through J. C. Bose fellowship. A.M. and V.K.M. gratefully acknowledge Council of Scientific and Industrial Research (CSIR), New Delhi for senior and junior research fellowships, respectively. We thank Dr. Savitha Govardhan for her help with refinement of some of the X-ray structures. Mr. Debanjan Bhattacharjee is thanked for his help during the initial stages of the project.
Publisher Copyright:
© 2016 American Chemical Society.
PY - 2016/9/2
Y1 - 2016/9/2
N2 - The fluoride-mediated desilylation reaction has been exploited, for the first time, to trigger ring-opening of photochromic diarylbenzo-/naphthopyrans into highly colored anionic merocyanine dyes with high molar absorptivities to permit naked-eye sensing. The absorption spectral shifts, i.e., differences in the absorption maxima of colorless and colored forms, observed for a rationally designed set of silyloxy-substituted diarylpyrans subsequent to fluoride-induced ring opening are remarkably high (330-480 nm), and are unknown for any colorimetric probe. In particular, the disilyloxy-substituted diphenylnaphthopyran and its analog, in which the diphenyl groups are fused in the form of fluorene, allows "naked-eye" detection of fluoride in subppm levels (<1.0 ppm) in THF as well as in DMSO-H2O. The sensing is specific for fluoride among various other anions. This approach for colorimetric sensing of fluoride by ring-opening of the otherwise photochromic benzo-/naphthopyrans is heretofore unprecedented.
AB - The fluoride-mediated desilylation reaction has been exploited, for the first time, to trigger ring-opening of photochromic diarylbenzo-/naphthopyrans into highly colored anionic merocyanine dyes with high molar absorptivities to permit naked-eye sensing. The absorption spectral shifts, i.e., differences in the absorption maxima of colorless and colored forms, observed for a rationally designed set of silyloxy-substituted diarylpyrans subsequent to fluoride-induced ring opening are remarkably high (330-480 nm), and are unknown for any colorimetric probe. In particular, the disilyloxy-substituted diphenylnaphthopyran and its analog, in which the diphenyl groups are fused in the form of fluorene, allows "naked-eye" detection of fluoride in subppm levels (<1.0 ppm) in THF as well as in DMSO-H2O. The sensing is specific for fluoride among various other anions. This approach for colorimetric sensing of fluoride by ring-opening of the otherwise photochromic benzo-/naphthopyrans is heretofore unprecedented.
UR - https://www.scopus.com/pages/publications/84984868897
U2 - 10.1021/acs.joc.6b01361
DO - 10.1021/acs.joc.6b01361
M3 - Article
AN - SCOPUS:84984868897
SN - 0022-3263
VL - 81
SP - 7741
EP - 7750
JO - Journal of Organic Chemistry
JF - Journal of Organic Chemistry
IS - 17
ER -