FRINK Linked Data Fragments server

Matches in SemOpenAlex for { <https://semopenalex.org/work/W1978268468> ?p ?o ?g. }

• W1978268468 endingPage "1832" @default.
• W1978268468 startingPage "1820" @default.
• W1978268468 abstract "The Leitner and Fürstner groups reported (Fürstner, A.; Koch, D.; Langemann, K.; Leitner, W.; Six, C. Angew Chem., Int. Ed. Engl. 1997, 36, 2466) on the ring closing metathesis (RCM) of a 16-membered diene dissolved in supercritical CO2 (scCO2). The authors found that the cyclic product, indicative of an intramolecular RCM event, was formed in excellent yield when the CO2 density was high, but oligomers were formed by an acyclic diene metathesis (ADMET) pathway at lower CO2 densities. These results suggest that changes in the CO2 density lead to changes in the intra- vs intermolecular interactions between the 16-membered diene dissolved in scCO2. To assess this issue in more detail, we have prepared 6-(1-pyrenyl)hexyl-11-(1-pyrenyl)undecanoate [1-Py(CH2)10COO(CH2)61-Py] in which we replaced the terminal alkenes of Letiner and Fürstner's original diene with the fluorophore pyrene. We have studied the pyrene excimer formation of 1-Py(CH2)10COO(CH2)61-Py when it is dissolved in five organic solvents (cyclohexane, dichloromethane, ethanol, acetonitrile, and dimethyl sulfoxide) and supercritical carbon dioxide (scCO2) to determine how the tail segments interact with each other. The result show that the excimer formation mechanism is completely different when 1-Py(CH2)10COO(CH2)61-Py is dissolved in scCO2 or organic liquids. In liquids, excimer formation is purely dynamic in nature, there are two formation pathways to the excimer, and all the rates can be understood with the help of Kamlet−Taft linear solvent energy relationships. In scCO2, we found that the 1-Py(CH2)10COO(CH2)61-Py excimer-to-monomer intensity ratio (E/M) correlates directly with (1) the observed RCM yield for Leitner and Fürstner's original 16-membered diene and (2) the solvent refractive index function. The steady-state and time-resolved fluorescence of 1-Py(CH2)10COO(CH2)61-Py dissolved in scCO2 show that there are two excimers that form in scCO2 and their relative contributions change in a systematic way with changes in the CO2 pressure/density. Interestingly, the typical dynamically formed excimer species that emits at 470−480 nm (E1) forms within 2 ns of optical excitation; however, it is not the dominant species at low CO2 densities. E1 is equivalent to the species that goes on to form the RCM product in Leitner and Fürstner's original reaction. The second excimer (E2) emits in the 410−440 nm region. E2 is associated with intermolecular preassociated forms of the pyrene residues within a collection of 1-Py(CH2)10COO(CH2)61-Py molecules, and this species dominates at low CO2 densities. E2 is equivalent to the species that goes on to form the oligomeric product in the original Leitner and Fürstner reaction. As the CO2 density increases, the E1 excimer contribution increases relative to the E2 excimer contribution. The combination of the fluorescence and reaction outcome results are used to explain Leitner and Fürstner's previous density-dependent RCM yields." @default.
• W1978268468 created "2016-06-24" @default.
• W1978268468 creator A5033523008 @default.
• W1978268468 creator A5036941968 @default.
• W1978268468 creator A5037352164 @default.
• W1978268468 creator A5040703058 @default.
• W1978268468 creator A5054667122 @default.
• W1978268468 creator A5069095946 @default.
• W1978268468 creator A5087961708 @default.
• W1978268468 date "2002-01-23" @default.
• W1978268468 modified "2023-10-06" @default.
• W1978268468 title "The Photophysics of 6-(1-Pyrenyl)hexyl-11(1-pyrenyl)undecanoate Dissolved in Organic Liquids and Supercritical Carbon Dioxide: Impact on Olefin Metathesis" @default.
• W1978268468 cites W1595800904 @default.
• W1978268468 cites W1964135724 @default.
• W1978268468 cites W1964245920 @default.
• W1978268468 cites W1965124772 @default.
• W1978268468 cites W1966092699 @default.
• W1978268468 cites W1966749100 @default.
• W1978268468 cites W1968681958 @default.
• W1978268468 cites W1981541153 @default.
• W1978268468 cites W1982520348 @default.
• W1978268468 cites W1982820843 @default.
• W1978268468 cites W1982874544 @default.
• W1978268468 cites W1989773692 @default.
• W1978268468 cites W1990767491 @default.
• W1978268468 cites W1993790948 @default.
• W1978268468 cites W1997254915 @default.
• W1978268468 cites W1998751557 @default.
• W1978268468 cites W2002824941 @default.
• W1978268468 cites W2002973015 @default.
• W1978268468 cites W2003543137 @default.
• W1978268468 cites W2009898994 @default.
• W1978268468 cites W2010755350 @default.
• W1978268468 cites W2011185745 @default.
• W1978268468 cites W2012185830 @default.
• W1978268468 cites W2012643870 @default.
• W1978268468 cites W2013795706 @default.
• W1978268468 cites W2022772216 @default.
• W1978268468 cites W2023833818 @default.
• W1978268468 cites W2023986840 @default.
• W1978268468 cites W2026457339 @default.
• W1978268468 cites W2040184556 @default.
• W1978268468 cites W2042143507 @default.
• W1978268468 cites W2042732987 @default.
• W1978268468 cites W2043055043 @default.
• W1978268468 cites W2043491418 @default.
• W1978268468 cites W2047248026 @default.
• W1978268468 cites W2048907968 @default.
• W1978268468 cites W2052650750 @default.
• W1978268468 cites W2053098921 @default.
• W1978268468 cites W2054001743 @default.
• W1978268468 cites W2056304033 @default.
• W1978268468 cites W2057003691 @default.
• W1978268468 cites W2058102838 @default.
• W1978268468 cites W2059605492 @default.
• W1978268468 cites W2067563803 @default.
• W1978268468 cites W2070223220 @default.
• W1978268468 cites W2072197372 @default.
• W1978268468 cites W2075009697 @default.
• W1978268468 cites W2078467325 @default.
• W1978268468 cites W2078908504 @default.
• W1978268468 cites W2085759071 @default.
• W1978268468 cites W2086247286 @default.
• W1978268468 cites W2088235037 @default.
• W1978268468 cites W2094164469 @default.
• W1978268468 cites W2094190449 @default.
• W1978268468 cites W2102595843 @default.
• W1978268468 cites W2111550991 @default.
• W1978268468 cites W2113587886 @default.
• W1978268468 cites W2116743364 @default.
• W1978268468 cites W2129995310 @default.
• W1978268468 cites W2143213238 @default.
• W1978268468 cites W2163671468 @default.
• W1978268468 cites W2175705688 @default.
• W1978268468 cites W2396619354 @default.
• W1978268468 cites W2502043876 @default.
• W1978268468 cites W2949649225 @default.
• W1978268468 cites W2949915978 @default.
• W1978268468 cites W2951590758 @default.
• W1978268468 cites W2953114696 @default.
• W1978268468 cites W3004874535 @default.
• W1978268468 cites W3005279877 @default.
• W1978268468 cites W4252021998 @default.
• W1978268468 cites W58458559 @default.
• W1978268468 cites W599412286 @default.
• W1978268468 doi "https://doi.org/10.1021/jp011497h" @default.
• W1978268468 hasPublicationYear "2002" @default.
• W1978268468 type Work @default.
• W1978268468 sameAs 1978268468 @default.
• W1978268468 citedByCount "33" @default.
• W1978268468 countsByYear W19782684682012 @default.
• W1978268468 countsByYear W19782684682013 @default.
• W1978268468 countsByYear W19782684682014 @default.
• W1978268468 countsByYear W19782684682015 @default.
• W1978268468 countsByYear W19782684682017 @default.
• W1978268468 countsByYear W19782684682018 @default.
• W1978268468 countsByYear W19782684682020 @default.
• W1978268468 countsByYear W19782684682022 @default.

• next