RESUMEN
Figure-eight-shaped nonplanar π-systems adopt distinctive chiral D2-symmetric structures, which are ideal for realizing efficient circularly polarized luminescence (CPL). However, the short-step and enantioselective synthesis of figure-eight π-systems represents a considerable challenge for the conventional bottom-up synthetic strategy. Herein, we report that the oxidative cleavage of the internal double bond of a commercially available polycyclic aromatic hydrocarbon, i.e., dibenzo[g,p]chrysene (DBC), catalytically affords a figure-eight electron-accepting macrocycle, i.e., cyclobisbiphenylenecarbonyl (CBBC), with high scalability (up to 3.3 g) and excellent enantioselectivity (94% ee). This inner-bond-cleavage approach also applies to larger PAHs, affording highly distorted molecular frameworks that comprise two figure-eight subunits. Furthermore, we demonstrate that the peripheral functionalization of CBBC with carbazole afforded donor-acceptor-type emitter, which shows thermally activated delayed fluorescence and emits CPL with a g value of 1.0 × 10-2. This g value is ten times higher than those of previously reported chiral TADF-active emitters for circularly polarized organic light-emitting diodes. These results demonstrate that oxidative inner-bond cleavage is a powerful synthetic strategy for creating innovative materials that incorporate molecules with figure-eight structures.
RESUMEN
Expanded carbohelicenes with structures fused to 15- and 17-benzene were successfully synthesized. Establishing a new synthetic strategy is crucial to realize the development of longer expanded [2,1][n]helicenes with a kekulene-like projection drawing structure. This article describes the sequential integration of the π-elongating Wittig reaction of functionalized phenanthrene units and ring-fusing Yamamoto coupling for the synthesis of [2,1][15]helicenes and [2,1][17]helicenes. X-ray crystallographic structures, photophysical properties, and density functional theory (DFT) calculations revealed the unique characteristics of the synthesized expanded helicenes. Furthermore, because of the high enantiomerization barrier derived from a wide-range intrahelix π-π interaction, the optical resolution of [2,1][17]helicene was successfully achieved, and chiroptical properties such as circular dichroism and circularly polarized luminescence were elucidated for the first time as enantiomers of pristine [2,1][n]helicene core.
RESUMEN
Hidradenitis suppurativa (HS) is a long-term inflammatory follicular disease. In Western countries, the prevalence of HS has been estimated to be 0.1-4% in the general population. In Okinawa Prefecture, the southernmost area of Japan, HS is more frequent than in other parts of Japan. The aim of this study is to elucidate the epidemiological features of HS patients in Okinawa, Japan, to determine the factors correlated with severity and to compare characteristics of HS patients in East Asia and Western countries. This study was a retrospective, single-center, case series study. Data of patients with HS diagnosed at the University of the Ryukyus Hospital from April 2010 to March 2019 were collected and compared with data of previous studies performed in Japan, Korea, France and the USA. There were 42 male and 16 female HS patients (age range, 15-76 years). The median modified Sartorius score was 49 (interquartile range, 87.3). A multivariate analysis indicated that disease duration was associated with the modified Sartorius score. The ratio of serum C-reactive protein to albumin was significantly correlated with disease severity (rs = 0.64, P < 0.001). Overall, in East Asia, HS was more common in males, and very few patients had a family history of HS (1.7% vs 29.1%, P < 0.001) compared with Western countries. This study revealed the characteristics of HS patients in Okinawa and elucidated the differences between the epidemiology of HS in Western countries and East Asia. In addition, we found out factors that correlated with disease severity such as disease duration and serum C-reactive protein to albumin ratio.