A Ti4+-exchanged montmorillonite (Ti4+-mont) and a hydrotalcite (HT) are strong solid Brønsted acid and base, and these two clay catalysts could be used in a single reactor without neutralization of active sites. Because the Ti4+-mont have active acid site in the narrow interlayers, the base sites of large HT particles show no interaction with the acid sites. A variety of acid and base reactions, such as esterification, acetalization, deacetalization, aldol reaction, Michael reaction, and epoxidation, proceeded using both the Ti4+-mont and the HT in a single reactor.

A ruthenium-grafted hydrotalcite (Ru/HT) and hydrotalcite-supported palladium nanoparticles (Pd(nano)/HT) are easily prepared by treating basic layered double hydroxide, hydrotalcite (HT, Mg(6)Al(2)(OH)(16)CO(3)) with aqueous RuCl(3)n H(2)O and K(2)[PdCl(4)] solutions, respectively, using surface impregnation methods. Analysis by means of X-ray diffraction, and energy-dispersive X-ray, electron paramagnetic resonance, and X-ray absorption fine structure spectroscopies proves that a monomeric Ru(IV) species is grafted onto the surface of the HT. Meanwhile, after reduction of a surface-isolated Pd(II) species, highly dispersed Pd nanoclusters with a mean diameter of about 70 A is observed on the Pd(nano)/HT surface by transmission electron microscopy analysis. These hydrotalcite-supported metal catalysts can effectively promote alpha-alkylation reactions of various nitriles with primary alcohols or carbonyl compounds through tandem reactions consisting of metal-catalyzed oxidation and reduction, and an aldol reaction promoted by the base sites of the HT. In these catalytic alpha-alkylations, homogeneous bases are unnecessary and the only by-product is water. Additionally, these catalyst systems are applicable to one-pot syntheses of glutaronitrile derivatives.

From the standpoint of atom efficiency, [1] nucleophilic additions to alkenes or alcohols instead of alkyl halides are attractive salt-free methods (Scheme 1). Simple alkenes are readily accessible and abundant carbon-atom sources, but intermolecular additions of 1,3-dicarbonyl compounds to simple alkenes remain problematic. In traditional acid-or base-catalyzed Michael reactions of 1,3-dicarbonyl com-

No abstract

4+ exchanged montmorillonite and a hydrotalcite catalyst system are used in a variety of acid and base reactions, such as esterification, acetalization, deacetalization, aldol reaction, Michael reaction, and epoxidation. The catalyst system is easy to prepare and shows high activity and wide applicability and reusability. -(MOTOKURA, K.; FUJITA, N.; MORI, K.; MIZUGAKI, T.; EBITANI, K.; KANEDA*, K.; J. Am. Chem. Soc. 127 (2005) 27, 9674-9675; Dep. Mater. Eng. Sci., Grad. Sch. Eng., Osaka Univ., Toyonaka, Osaka 560, Japan; Eng.) -S. Adam 47-050

No abstract

Five new monomers of transition metal complexes containing a styryl group, trans‐\documentclass{article}\pagestyle{empty}\begin{document}$ {\rm Pd}({\rm PBu}_{\rm 3})_2 \rlap{--} ({\rm C}_6 {\rm H}_4 {\rm CH} \hbox{=\hskip-2pt=} {\rm CH}_2 ){\rm X\ X \hbox{=\hskip-2pt=} Cl(Ia),\ X \hbox{=\hskip-2pt=} Br(Ib)},\ {\rm X \hbox{=\hskip-2pt=} CN(Ic),\ X \hbox{=\hskip-2pt=} Ph(Id)} $\end{document} and trans‐\documentclass{article}\pagestyle{empty}\begin{document}${\rm Pt(PBu}_{\rm 3} {\rm )}_{\rm 2} \rlap{--} ({\rm C}_{\rm 6} {\rm H}_{\rm 4} {\rm CH} \hbox{=\hskip-2pt=} {\rm CH}_2 ){\rm Cl}({\rm II})$\end{document}, were synthesized. The monomers were readily homopolymerized in benzene with the use of AIBN or BBu3–oxygen as the initiator. Copolymerization of Ia with styrene was carried out by using AIBN. From the Cl content of the copolymers by analysis, monomer reactivity ratios and Q–e values were obtained as follows: r1 = 1.49, r2 = 0.45; Q2 = 0.41, e2 = −1.4 (M1 = styrene, M2 = Ia). Based on the above data, the σ‐bonded palladium moiety at para position of styrene acts as a strongly electron‐donating group to the phenyl ring. This is also supported by the olefinic β‐carbon chemical shift of 13C NMR for Ia.

Purpose Studies in adults have reported that video laryngoscope is more useful than direct laryngoscope when training less experienced anesthesiologists. However, whether this is true for infants remains unclear. Therefore, this study aimed to evaluate whether the use of video laryngoscope would result in smaller differences in success rate according to anesthesiologists’ expertise than those in direct laryngoscope. Methods Medical records and video recordings from the operating room of patients aged < 1 year who underwent non-cardiac surgery between March 2019 and September 2021 were reviewed. Tracheal intubations between April 8, 2020, and June 20, 2021, were excluded due to the shortage of video laryngoscope blades during the COVID-19 pandemic. Rates of first-time tracheal intubation success were compared by years of anesthesia experience and initial intubation device. Results In total, 125 of 175 tracheal intubations were analyzed (direct laryngoscope group, n = 72; video laryngoscope group, n = 53). The first-time tracheal intubation success rate increased with years of experience as an anesthesiologist in the direct laryngoscope group (odds ratio OR 1.70, 95% confidence interval CI 1.15, 2.49; P = 0.0070), but not the video laryngoscope group (OR 0.99, 95% CI 0.74, 1.35; P = 0.99). Conclusion The differences in success rate according to the anesthesiologists’ years of experience were non-significant when using video laryngoscope in infants, compared to those in direct laryngoscope. Supplementary Information The online version contains supplementary material available at 10.1007/s00540-022-03106-y.