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Dirhodium(II) tetrakis[N-tetrafluorophthaloyl-(S)-tert-leucinate], Rh2[(S)-TFPTTL]4, in which the phthalimido hydrogen atoms of the parent dirhodium(II) complex are substituted by fluorine atoms, dramatically enhances the reactivity and enantioselectivity (up to 97% ee) in intramolecular aromatic C–H insertion reactions of methyl 4-alkyl-2-diazo-4,4-diphenyl-3-oxopropionates. Catalysis with the use of 0.001 mol% of Rh2[(S)-TFPTTL]4 has achieved the highest turnover number (up to 98,000 with the methyl substituent) ever recorded for chiral dirhodium(II) complex-catalyzed carbene transformations, without compromising the yield or enantioselectivity of the process. [Copyright &y& Elsevier]

Abstract: More elaborated specimen preparation techniques for atom probe analysis were developed using a focused ion beam with a sample lift-out system so as to expand the application field in steel materials. The techniques enable atom probe analysis of sample steel at site-specific regions of interest. The preferable form of the needle specimen was provided by electrostatic field calculation using a finite element method. The new techniques were applied to the observation of a bainite–ferrite interface in a low carbon steel, and atomic-scale partitioning and segregation of alloying elements at the phase interface were directly observed in three dimensions. [Copyright &y& Elsevier]

A catalytic, enantioselective Michael addition of β-keto esters to α,β-unsaturated carbonyl compounds was achieved by using a chiral biquinoline N,N′-dioxide–scandium trifluoromethanesulfonate complex as a catalyst. The corresponding Michael adducts were obtained in high yields and with enantioselectivities up to 84% ee. [Copyright &y& Elsevier]