Absorption and redox properties of seven decakis(phenylthio)corannulene derivatives 3a–3g lead to... more Absorption and redox properties of seven decakis(phenylthio)corannulene derivatives 3a–3g lead to a model for estimating material properties in persulfurated aromatic compounds. The same series is evaluated for performance in bulk heterojunction and perovskite photovoltaic devices.
Ten sym‐penta and deca‐X substituted corannulenes (1–10; X=H, F, CH3, or CF3) define a library of... more Ten sym‐penta and deca‐X substituted corannulenes (1–10; X=H, F, CH3, or CF3) define a library of fluorous compounds comprising high symmetry non‐planar aromatic compunds. They provide a group of structurally similar, yet physically distinct structures manifesting special chemical behavior related to their degree of fluorination. Owing to their bowl forms, corannulene derivatives are distinct from planar polynuclear aromatic compounds; they have relatively high dipole moments, accept 1–4 electrons, and display room temperature fluorescence as well as low temp phosphorescence. Electronic structure theory predicts the bowl inversion barrier and physical properties. The syntheses of sym‐pentafluorocorannulene by an efficient late stage fluorination affords a key derivative to calibrate predictions.
Chiral corannulenes abound, but suffer generally from configurational lability associated with bo... more Chiral corannulenes abound, but suffer generally from configurational lability associated with bowl‐to‐bowl inversion, thus obviating questions of stereogenicity and stereoelement construction. In contrast, peri‐annulated corannulenes show greatly increased barriers for bowl‐to‐bowl inversion; specifically indenocorannulenes invert on a time scale too slow to observe by normal NMR methods and raise the possibility of creating chiral atropisomeric bowl‐shaped aromatics. Two methods for preparing indenocorannulene from simple 2‐haloarylcorannulenes—silyl cation C–F activation, and Pd‐mediated C–Cl activation[5]—enable the synthesis of an array of such chiral atropisomeric indenocorannulenes. Resolution of the enantiomers by high‐performance liquid chromatography over chiral support phases motivates the study of chiroptical properties, the assignment of absolute “Cartesian” configuration, and the assessment of configurational stability. These studies bring into question any systematic ...
Silyl cation-promoted aryl C–F activation can lead to formal C–H activation and the formation of ... more Silyl cation-promoted aryl C–F activation can lead to formal C–H activation and the formation of new C(ar)–C(alkyl) bonds.
Carbon fluorine bond activation produces phenyl cations that are effective electrophiles for a ne... more Carbon fluorine bond activation produces phenyl cations that are effective electrophiles for a new synthesis of tetraarylammonium and triaryloxonium ions. In parallel with diazonium salt decomposition a robust and general method to these underrepresented cations is demonstrated in this work.
Graph theory and isosteric replacement leads to the design and synthesis of (chiral) thiophene-fu... more Graph theory and isosteric replacement leads to the design and synthesis of (chiral) thiophene-fused indenocorannulenes with exceptional configurational stability and possible use as chiral catalysts, chiroptical materials, and sensors.
Condensed phosphates may exist as linear, cyclic or branched structures. Due to their important r... more Condensed phosphates may exist as linear, cyclic or branched structures. Due to their important role in nature, linear polyphosphates have been well studied. In contrast, branched phosphates (ultraphosphates) remain largely uncharacterised, because they were already described in 1950 as exceedingly unstable in the presence of water, epitomized in the antibranching-rule. This rule lacks experimental backup, since, to the best of our knowledge, no rational synthesis of defined ultraphosphates is known. Consequently, detailed studies of their chemical properties, reactivity and potential biological relevance remain elusive. Here, we introduce a general synthesis of monodisperse ultraphosphates. Hydrolysis half-lives up to days call the antibranching-rule into question. We provide evidence for the interaction of an enzyme with ultraphosphates and discover a rearrangement linearizing the branched structure. Moreover, ultraphosphate can phosphorylate nucleophiles such as amino acids and n...
Experimental optical absorption and photoconductivity spectra of thin films with GW–BSE theoretic... more Experimental optical absorption and photoconductivity spectra of thin films with GW–BSE theoretical predictions provide evidence for diffuse super atomic molecular orbitals (SAMOs) in corannulene, C20H10.
Jay S. Siegel received his Ph.D. from Princeton (1985), was a Swiss Universities Fellow at ETH Zu... more Jay S. Siegel received his Ph.D. from Princeton (1985), was a Swiss Universities Fellow at ETH Zurich (1983-4), and NSF–CNRS postdoctoral fellow at the University of Louis Pasteur in Strasbourg (1985-6). He began as Assistant Professor of Chemistry (1986) at UCSD, was promoted to Associate Professor (1992) and Full Professor (1996). In 2003, he was appointed as Professor and co-director of the Organic chemistry institute of the University of Zurich (UZH) and Director of its laboratory for process chemistry research (LPF). He served as Dean of Studies and Head of the Research Council for the Faculty of Sciences at UZH. He moved to Tianjin University in 2013 as dean and joined the Schools of Pharmaceutical and Life Sciences into a new Health Science Platform. His research is in the area of Stereochemistry and Physical Organic Chemistry.
Absorption and redox properties of seven decakis(phenylthio)corannulene derivatives 3a–3g lead to... more Absorption and redox properties of seven decakis(phenylthio)corannulene derivatives 3a–3g lead to a model for estimating material properties in persulfurated aromatic compounds. The same series is evaluated for performance in bulk heterojunction and perovskite photovoltaic devices.
Ten sym‐penta and deca‐X substituted corannulenes (1–10; X=H, F, CH3, or CF3) define a library of... more Ten sym‐penta and deca‐X substituted corannulenes (1–10; X=H, F, CH3, or CF3) define a library of fluorous compounds comprising high symmetry non‐planar aromatic compunds. They provide a group of structurally similar, yet physically distinct structures manifesting special chemical behavior related to their degree of fluorination. Owing to their bowl forms, corannulene derivatives are distinct from planar polynuclear aromatic compounds; they have relatively high dipole moments, accept 1–4 electrons, and display room temperature fluorescence as well as low temp phosphorescence. Electronic structure theory predicts the bowl inversion barrier and physical properties. The syntheses of sym‐pentafluorocorannulene by an efficient late stage fluorination affords a key derivative to calibrate predictions.
Chiral corannulenes abound, but suffer generally from configurational lability associated with bo... more Chiral corannulenes abound, but suffer generally from configurational lability associated with bowl‐to‐bowl inversion, thus obviating questions of stereogenicity and stereoelement construction. In contrast, peri‐annulated corannulenes show greatly increased barriers for bowl‐to‐bowl inversion; specifically indenocorannulenes invert on a time scale too slow to observe by normal NMR methods and raise the possibility of creating chiral atropisomeric bowl‐shaped aromatics. Two methods for preparing indenocorannulene from simple 2‐haloarylcorannulenes—silyl cation C–F activation, and Pd‐mediated C–Cl activation[5]—enable the synthesis of an array of such chiral atropisomeric indenocorannulenes. Resolution of the enantiomers by high‐performance liquid chromatography over chiral support phases motivates the study of chiroptical properties, the assignment of absolute “Cartesian” configuration, and the assessment of configurational stability. These studies bring into question any systematic ...
Silyl cation-promoted aryl C–F activation can lead to formal C–H activation and the formation of ... more Silyl cation-promoted aryl C–F activation can lead to formal C–H activation and the formation of new C(ar)–C(alkyl) bonds.
Carbon fluorine bond activation produces phenyl cations that are effective electrophiles for a ne... more Carbon fluorine bond activation produces phenyl cations that are effective electrophiles for a new synthesis of tetraarylammonium and triaryloxonium ions. In parallel with diazonium salt decomposition a robust and general method to these underrepresented cations is demonstrated in this work.
Graph theory and isosteric replacement leads to the design and synthesis of (chiral) thiophene-fu... more Graph theory and isosteric replacement leads to the design and synthesis of (chiral) thiophene-fused indenocorannulenes with exceptional configurational stability and possible use as chiral catalysts, chiroptical materials, and sensors.
Condensed phosphates may exist as linear, cyclic or branched structures. Due to their important r... more Condensed phosphates may exist as linear, cyclic or branched structures. Due to their important role in nature, linear polyphosphates have been well studied. In contrast, branched phosphates (ultraphosphates) remain largely uncharacterised, because they were already described in 1950 as exceedingly unstable in the presence of water, epitomized in the antibranching-rule. This rule lacks experimental backup, since, to the best of our knowledge, no rational synthesis of defined ultraphosphates is known. Consequently, detailed studies of their chemical properties, reactivity and potential biological relevance remain elusive. Here, we introduce a general synthesis of monodisperse ultraphosphates. Hydrolysis half-lives up to days call the antibranching-rule into question. We provide evidence for the interaction of an enzyme with ultraphosphates and discover a rearrangement linearizing the branched structure. Moreover, ultraphosphate can phosphorylate nucleophiles such as amino acids and n...
Experimental optical absorption and photoconductivity spectra of thin films with GW–BSE theoretic... more Experimental optical absorption and photoconductivity spectra of thin films with GW–BSE theoretical predictions provide evidence for diffuse super atomic molecular orbitals (SAMOs) in corannulene, C20H10.
Jay S. Siegel received his Ph.D. from Princeton (1985), was a Swiss Universities Fellow at ETH Zu... more Jay S. Siegel received his Ph.D. from Princeton (1985), was a Swiss Universities Fellow at ETH Zurich (1983-4), and NSF–CNRS postdoctoral fellow at the University of Louis Pasteur in Strasbourg (1985-6). He began as Assistant Professor of Chemistry (1986) at UCSD, was promoted to Associate Professor (1992) and Full Professor (1996). In 2003, he was appointed as Professor and co-director of the Organic chemistry institute of the University of Zurich (UZH) and Director of its laboratory for process chemistry research (LPF). He served as Dean of Studies and Head of the Research Council for the Faculty of Sciences at UZH. He moved to Tianjin University in 2013 as dean and joined the Schools of Pharmaceutical and Life Sciences into a new Health Science Platform. His research is in the area of Stereochemistry and Physical Organic Chemistry.
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