KEY WORDSLong-Lived Propagating Species / Rhodium Complex Catalyst / m-Chlorophenylacetylene / In recent years there has been a growing interest in the polymerization of aromatic acetylenes using transition metal catalysts. Several investigations have been described in the literature, 1 -4 including the living polymerization of ortho substituted phenylacetylenes by Mo-based catalyst. In our preliminary experiments, the polymerization of chlorinated phenylacetylenes, for example, o-chlorophenylacetylene ( o-CPA), m-chlorophenylacetylene (m-CPA) and pchlorophenylacetylene (p-CPA) in the presence of Rh complex-TEA catalyst was examined. Among their monomers, m-CPA was readily polymerized to quantitative conversion and the polydispersity of the resultant polymer, Poly-(m-CPA) soluble into common solvents was rather narrow. Therefore, the polymerization of m-CPA was studied using three kinds of Rh-based catalysts, i.e., Rh-TEA

Phenylacetylene and its homologues bearing methoxy or chloro groups in the para position of the phenyl ring were stereoregularly polymerized by Rh complex catalysts, e.g., [Rh (norbornadiene) Cl]2, in the presence of various solvents. The 1H‐NMR and UV study of the Rh complex showed that the activity of the Rh catalysts greatly depends upon not only the ligand in the Rh catalyst but also on the solvent used, e.g., polyphenylacetylene with a highly cis‐transoidal content was quantitatively obtained when norbornadiene was coordinated as the ligand, and triethylamine (TEA) was used as solvent, whereas tetrahydrofuran (THF) and benzene reduced the cis content. It was also found that the Rh catalyst as a dimer complex dissociates into the monomeric species not only when TEA was used but also when alcohol, benzene, and THF were used. The resulting monomeric species was considered as the important propagation species in this polymerization. The sharp line width observed in the 1H‐NMR spectrum of polyphenylacetylene and its homologues which were prepared in ethanol or TEA was interpreted by the narrow chemical shift distribution arising from the high cis content. © 1994 John Wiley & Sons, Inc.

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Using three European and two Chinese genome-wide association studies (GWAS), we investigated the performance of genetic risk scores (GRSs) for predicting the susceptibility and severity of systemic lupus erythematosus (SLE), using renal disease as a proxy for severity. We used four GWASs to test the performance of GRS both cross validating within the European population and between European and Chinese populations. The performance of GRS in SLE risk prediction was evaluated by receiver operating characteristic (ROC) curves. We then analyzed the polygenic nature of SLE statistically. We also partitioned patients according to their age-of-onset and evaluated the predictability of GRS in disease severity in each age group. We found consistently that the best GRS in the prediction of SLE used SNPs associated at the level of P < 1e−05 in all GWAS data sets and that SNPs with P-values above 0.2 were inflated for SLE true positive signals. The GRS results in an area under the ROC curve ranging between 0.64 and 0.72, within European and between the European and Chinese populations. We further showed a significant positive correlation between a GRS and renal disease in two independent European GWAS (Pcohort1 = 2.44e−08; Pcohort2 = 0.00205) and a significant negative correlation with age of SLE onset (Pcohort1 = 1.76e−12; Pcohort2 = 0.00384). We found that the GRS performed better in the prediction of renal disease in the ‘later onset’ compared with the ‘earlier onset’ group. The GRS predicts SLE in both European and Chinese populations and correlates with poorer prognostic factors: young age-of-onset and lupus nephritis.

A rational designed Ir­(III)-catalyzed enantioselective C–H amidation of dibenzyl sulfoxides through desymmetrization and parallel kinetic resolution is demonstrated. An Ir­(III) complex equipped with a t-butyl cyclopentadienyl ligand and paired with a modified chiral proline enables the highly enantioselective sulfoxide-steered C–H bond activation, providing an efficient and straightforward way to construct sulfur chiral centers. A wide range of dibenzyl sulfoxides and dioxazolones are compatible with this process, giving access to a variety of highly functionalized sulfoxide compounds with synthetically attractive amide substitution groups in good yields and enantioselectivities. Moreover, the flexible derivatization of the amidated sulfoxide was elaborated, providing various types of chiral sulfoxide scaffolds that would be potentially useful in asymmetric catalysis as chiral bidentate and tridentate ligands.

Polymers with functional end groups are synthesized using a cyclic lactone ATRP initiator for honeycomb-patterned porous films by the breath figure method.

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Ar hodium(I)-catalyzed enantioselective silylation of aliphatic C À Hbonds for the synthesis of silicon-stereogenic dihydrobenzosiloles is demonstrated. This reaction involves ahighly enantioselective intramolecular C(sp 3)ÀHsilylation of dihydrosilanes,f ollowed by as tereospecific intermolecular alkene hydrosilylation leading to the asymmetrically tetrasubstituted silanes.Awide range of dihydrosilanes and alkenes displaying various functional groups are compatible with this process,g iving access to av ariety of highly functionalized silicon-stereogenic dihydrobenzosiloles in good to excellent yields and enantioselectivities. Scheme 1. Enantioselective silylation of aliphaticC ÀHbonds.