17049-49-9Relevant articles and documents
Organic Thin-film Solar Cells Using Benzotrithiophene Derivatives Bearing Acceptor Units as Non-Fullerene Acceptors
Matsumoto, Kouichi,Yamashita, Kazuhiro,Sakoda, Yuuki,Ezoe, Hinata,Tanaka, Yuki,Okazaki, Tatsuya,Ohkita, Misaki,Tanaka, Senku,Aoki, Yuki,Kiriya, Daisuke,Kashimura, Shigenori,Maekawa, Masahiko,Kuroda-Sowa, Takayoshi,Okubo, Takashi
, p. 4620 - 4629 (2021/09/10)
New star-shaped non-fullerene acceptors (5Z,5′Z,5′′Z)-5,5′,5′′-((benzo[1,2-b : 3,4-b′ : 5,6-b′′]trithiophene-2,5,8-triyltris(4-octylthiophene-5,2-diyl))tris(methaneylylidene))tris(3-octyl-2-thioxothiazolidin-4-one) (1: BTT-OT-ORD) and 2,2′,2′′-((5Z,5′Z,5′′Z)-((benzo[1,2-b : 3,4-b′ : 5,6-b′′]trithiophene-2,5,8-triyltris(4-octylthiophene-5,2-diyl))tris(methaneylylidene))tris(3-octyl-4-oxothiazolidine-5,2-diylidene))trimalononitrile (2: BTT-OT-OTZDM) with a benzotrithiophene core, alkyl-thiophen units, and acceptor units were designed and synthesized. The HOMO-LUMO levels of 1 and 2 were determined by photoemission spectroscopy and UV-Vis absorption spectroscopy. Binary blend and ternary blend bulk heterojunction (BHJ) organic solar cells with non-fullerene acceptors 1 and 2 were fabricated with the inverted device structures of glass/ITO/ZnO/active_layer/MoO3/Ag. Both binary blend BHJ solar cells with 1 and 2 show lower JSC and larger VOC values than P3HT : PCBM solar cells. On the other hand, ternary blend BHJ organic solar cells, including 10 % of 1, exhibited a larger power conversion efficiency than P3HT : PCBM solar cells because the JSC value was largely improved.
Reversible Formation of Alkyl Radicals at [Fe4S4] Clusters and Its Implications for Selectivity in Radical SAM Enzymes
Brown, Alexandra C.,Suess, Daniel L. M.
supporting information, p. 14240 - 14248 (2020/09/15)
All kingdoms of life use the transient 5′-deoxyadenosyl radical (5′-dAdoa ) to initiate a wide range of difficult chemical reactions. Because of its high reactivity, the 5′-dAdo?must be generated in a controlled manner to abstract a specific H atom and avoid unproductive reactions. In radical S-Adenosylmethionine (SAM) enzymes, the 5′-dAdo?is formed upon reduction of SAM by an [Fe4S4] cluster. An organometallic precursor featuring an Fe-C bond between the [Fe4S4] cluster and the 5′-dAdo group was recently characterized and shown to be competent for substrate radical generation, presumably via Fe-C bond homolysis. Such reactivity is without precedent for Fe-S clusters. Here, we show that synthetic [Fe4S4]-Alkyl clusters undergo Fe-C bond homolysis when the alkylated Fe site has a suitable coordination number, thereby providing support for the intermediacy of organometallic species in radical SAM enzymes. Addition of pyridine donors to [(IMes)3Fe4S4-R]+ clusters (R = alkyl or benzyl; IMes = 1,3-dimesitylimidazol-2-ylidene) generates Ra , ultimately forming R-R coupled hydrocarbons. This process is facile at room temperature and allows for the generation of highly reactive radicals including primary carbon radicals. Mechanistic studies, including use of the 5-hexenyl radical clock, demonstrate that Fe-C bond homolysis occurs reversibly. Using these experimental insights and kinetic simulations, we evaluate the circumstances in which an organometallic intermediate can direct the 5′-dAdo?toward productive H-Atom abstraction. Our findings demonstrate that reversible homolysis of even weak M-C bonds is a feasible protective mechanism for the 5′-dAdo?that can allow selective X-H bond activation in both radical SAM and adenosylcobalamin enzymes.
Configurational Assignment of ‘Cryptochiral’ 10-Hydroxystearic Acid Through an Asymmetric Catalytic Synthesis
Brunner, Andreas,Hintermann, Lukas
, p. 928 - 943 (2016/12/09)
An asymmetric catalytic total synthesis of (S)-10-hydroxystearic acid (1) for comparison of its absolute configuration to that of samples obtained by fermentative hydration of oleic acid is reported. The synthesis involves two catalytic key-steps, namely Ru-catalyzed anti-Markovnikov hydration of 9-decynoic acid (7) to 10-oxodecanoic acid (5), followed by titanium-mediated asymmetric catalytic addition of dioctylzinc (25) to 5 in presence of the chiral ligand N,N’-((1R,2R)-cyclohexane-1,2-diyl)bis(1,1,1-trifluoromethanesulfonamide) (6). The synthesis is short and efficient and avoids use of protecting groups. Ozonolysis of 10-undecynoic acid (9) to 5 provides an alternative entry point into the synthetic route. The double dehydrobromination of (ω,ω-1)-dibromoalkanoic acids to ω-alkynoic acids under a variety of conditions was investigated with 10,11-dibromoundecanoic acid (11) as model substrate and using qNMR to quantify all reaction products. The synthetic approaches presented here have the potential to be generalized to the asymmetric catalytic synthesis of a variety of n-hydroxy-fatty acids.