4th EucheMs chemistry congress

Poster Session 2
s1349
chem. Listy 106, s257–s1425 (2012)
Poster session 2 - organic chemistry
P - 0 9 7 3
CoPPer CAtALyzed AryLAtion of
AryLethynyL-PiviLAniLideS viC C-h
ACtivAtion
A. SinAi 1 , A. MeSzAroS 1 , z. novAK 1
1 Eotvos Lorand University, Institute of Chemistry, Budapest,
Hungary
Transition metal catalyzed C-H activation is one of the most
important synthetic tools in recent organic chemistry.
Functionalization of aromatic systems bearing directing groups
can be achieved most frequently with palladium or copper
catalysts. Beside several coupling partners, diaryl iodonium salts
are used as aryl transfer reagents. With the utilization of
hypervalent iodine compounds anilides can be functionalized in
orto or meta position depending on the applied catalyst. Recently
Gaunt discovered the meta selective arylation of anilides with
diaryl iodonium salts in the presence of copper. [1]
The poster presentation will discuss our recent results on the
functionalization of o-arylethynyl-anilides with diaryl iodonium
salts in copper(II)-triflate catalyzed C-H functionalization.
references:
1. Phipps, R. J. Gaunt, M. J. Science, 2009, 323, 1593-1597.
Keywords: C-H activation; copper; Iodine; Aromatic
substitution; palladium;
4 th EucheMs chemistry congress
P - 0 9 7 4
fLuoreSCenCe BASed MetAL ion deteCtion By
ALKyL/AryL PyrenyL SuLfoxideS
r. S. KAthAyAt 1
1 Organic Chemistry Institute, Organic Chemistry, Zürich,
Switzerland
Chemosensors are molecules which respond to binding
analytes of interest by changes in its colourimetric, photophysical,
electrochemical properties. Fluorescence being a very sensitive
and non-invasive technique is well suited for chemosensing.
Fluorescent chemosensors for ions have been widely used to
monitor ions’ concentrations in biological, environmental and
biomedical assays. Most such fluorionophores are based on
signaling mechanisms like photoinduced electron transfer (PET),
intramolecular charge transfer(ICT) or binding-induced
conformational restriction [1] . Prevention of photoinduced electron
transfer by oxidation of sulfoxide to corresponding sulfone has
been used to detect oxidant analytes e.g. Triacetone triperoxide
(TATP) [2] . Interestingly, oxidation of sulfide to corresponding
sulfoxide leads to decrease in fluorescence quantum yield, an
observation which cannot be explained by PET quenching [3] .
These less fluorescent sulfoxides provide an opportunity to
develop fluorescent chemosensors based on fluorescence recovery
upon ion binding by the sulfoxide. A series of alkyl/aryl pyrenyl
sulfoxide were synthesized and found to exhibit fluorescence
enhancement with Zn2+ and Li + , and reduction with Fe3+ metal
ions.
references:
1. Sergey A. Malashikhin, Kim K. Baldridge,
Nathaniel S. Finney, Org. Lett. 2010, 12, 940-943.
2. Sergey A. Malashikhin, Nathaniel S. Finney, J. Am. Chem.
Soc. 2008, 130, 12846-12847.
3. a) Yushen Guo, William S. Jenks, J. Org. Chem. 1995, 60,
5480-5486.
b) Brian W. Vos, William S. Jenks, J. Am. Chem. Soc.
2002, 124, 2544-2547.
Keywords: Chemosensors; Fluorescence; alkyl/aryl pyrenyl
sulfoxides;
AUGUst 26–30, 2012, PrAGUE, cZEcH rEPUbLIc