Dual‐Context Sequent Calculus and Strict Implication

We introduce a dual‐context style sequent calculus which is complete with respectto Kripke semantics where implication is interpreted as strict implication in the modal logic K. The cut‐elimination theorem for this calculus is proved by a variant of Gentzen's method.     

Synthesis of Highly Emissive Fluorophores Based on Multiply Stacked Anthracene Arrangement

Newly designed fluorophore systems with feather-like structures were constructed by connecting bisanthracene building units via a concise reaction sequence of bromination, etherification, and desilylation. Spectroscopic characterizations revealed that all of the fluorophore systems achieved high light absorptivity and high emission efficiency by preventing closely spaced anthracene chromophores from mutual interactions to reduce concomitant energy loss by fluorescence quenching. The application of fluorophore systems for the preparation of light-harvesting dyad materials has successfully demonstrated their potential utility as versatile photofunctional tools.     

Synthesis and properties of optically active phosphine-boranes possessing an l-menthyloxy group

(SP)-9-Anthryl(l-menthyloxy)phenylphosphine-borane and (SP)-(1-l-menthyloxy)benzo[b]phosphole-borane were synthesized, and their structures were characterized by X-ray crystallographic analysis. The latter compound was reduced by lithium naphthalenide at −78°C with cleavage of the P O bond, and the subsequent reaction with electrophiles afforded the corresponding tertiary phosphine-boranes possessing good to excellent enantiomeric excesses.     

Synthesis of Isomeric Tb3+-Phthalocyanine Double-Decker Complexes Depending on the Difference in the Direction of Coordination Plane and Their Magnetic Properties

A C_4h symmetrically substituted phthalocyanine, 1,8,15,22-tertrakis(2,4-dimethylpent-3-oxy)phthalocyanine (H₂TdMPPc), was used to synthesize Tb³⁺-phthalocyanine double-decker complexes ([Tb(TdMPPc)₂]s). Because H₂TdMPPc has C_4h symmetry, S,S, R,R, and meso isomers of [Tb(TdMPPc)₂] were obtained depending on the difference in the direction of the coordination plane of two C_4h-type phthalocyanines with respect to a central Tb³⁺ ion. We investigated the physical properties of these [Tb(TdMPPc)₂] isomers, including their single-ion magnetic properties, and found that the spin-reversal energy barrier (U_eff) of the meso isomer was apparently higher than that of the enantiomers. Detailed crystal structural analyses indicated that the meso isomer has a more symmetrical structure than do the enantiomers, thereby suggesting that the higher U_eff of the meso isomer originated from the more highly symmetrical structure.