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Abstract The design of bright, high quantum yield (QY) materials in the near‐infrared (NIR) spectral region in water remains a significant challenge. A series of cyanine and squaraine dyes varying water solubilizing groups and heterocycles are studied to probe the interactions of these groups with albumin in water. Unprecedented, ′ultra‐bright′ emission in water is observed for a sulfonate indolizine squaraine dye (61.1 % QY) and a sulfonate indolizine cyanine dye (46.7 % QY) at NIR wavelengths of >700 nm and >800 nm, respectively. The dyes presented herein have a lower limit of detection than the most sensitive dyes known in the NIR region for albumin detection by at least an order of magnitude, which enables more sensitive diagnostic testing. Additionally, biotinylated human serum albumin complexed with the dyes reported herein was observed to function as an immunohistochemical reagent enabling high resolution imaging of cellular α‐tubulin at low dye concentrations.
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Desymmetrization of Cyclic Sulfonimidamides by Asymmetric Allylation
Abstract Herein we report the first transition metal‐catalyzed approach to the enantioenriched synthesis of cyclic sulfonimidamides relying on commercially available palladium catalysts and ligands. High‐throughput experimentation (HTE) was employed to identify the optimal catalyst system and solvent. The method is applied to a variety of saturated and unsaturated rings and exhibits the highest selectivity for 2‐substituted allyl electrophiles. The products are further elaborated to complex, tricyclic scaffolds. DFT experiments presented herein highlight the key ligand substrate interactions leading to the high levels of enantioselectivity.
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- Award ID(s):
- 2247324
- PAR ID:
- 10523036
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Angewandte Chemie International Edition
- Volume:
- 63
- Issue:
- 34
- ISSN:
- 1433-7851
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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