Dedication

Professor Fumio Toda

Koichi Tanaka

Department of Applied Chemistry, Faculty of Engineering, Ehime University, Matsuyama, Ehime 790-8577, Japan

Professor Fumio Toda was born in Kochi, Japan, in 1933.He received his Bachelor, Masters, and Doctoratedegrees from Osaka University in 1956, 1958 and 1960respectively. After staying at Osaka University for fouryears as an Instructor and in the United States for twoyears as a postdoctoral fellow (Prof. Nelson Leonard,University of Illinois), he obtained an Associate Profes-sorship at Ehime University in 1966. He was promoted tofull Professor in 1972.

Professor Toda has developed new research fields ofmolecular recognition and reactions in the solid state. Hisnew solid state chemistry is mainly based on his findingsof easy molecular movement and chiral arrangement ofachiral molecules in the solid state, and designing ofsimple new chiral host compounds. Using a combinationof these findings, interesting new chiral separation andchiral synthetic methods were developed.

In 1968, he found that 1,1,6,6-tetraphenyl-2,4-hexa-diyn-1,6-diol (1) forms stable inclusion complexes withvarious guest compounds in stoichiometric ratios. X-raystructures of some inclusion complexes of1 suggestedthat alcohols with sterically bulky substituents and rigidmolecular frameworks might become good host com-pounds. Based on this idea he developed many newsimple hosts including several chiral host compounds.Using these simple host compounds, he established a newseparation method by inclusion crystallization. By usingenantioselective inclusion complexation with a chiralhost, new simple optical resolution methods of racemicguests have been developed. Since inclusion complexa-tion can be accomplished for both polar and non-polarcompounds, various types of guest compounds, evenhydrocarbons, can be resolved easily. In some cases,racemic compounds were resolved by fractional distilla-tion in the presence of a chiral host. By mixing of a chiralhost and a racemic guest in the absence of a solvent, oneenantiomer forms an inclusion complex with the chiralhost, and the uncomplexed chiral guest distils atrelatively low temperature. By further heating at arelatively high temperature, the inclusion complex isdecomposed to release the other enantiomer which can bedistilled out. This is a really elegant separation methodfor enantiomers and is useful especially in industry. Next,he developed a new method for stereoselective reactionsin the inclusion crystals. Both photochemical andthermochemical reactions can be applied for enantiose-

lective synthesis in the inclusion crystal of prochiralguests with a chiral host. Most of these reactions proceedefficiently to give chiral products in high optical andchemical yields. Some reactions proceed from singlecrystal to single crystal. He also prepared chiral crystalsof achiral molecules, which upon photoirradiation givethe chiral product. These phenomena provided anotherfundamental idea for the chiral arrangement of achiralmolecules in crystals and for absolute chiral synthesis inthe solid state.

In 1987, Prof. Toda found that inclusion complexationoccurs by simple mixing and grinding of powdered hostand guest compounds. Guided by this observation hedemonstrated most organic reactions occur efficiently inthe solid state. In many cases, solid-state organicreactions occur more efficiently and more selectivelythan those in solution. Thus, he opened up a new field ofsolid-state organic chemistry. Surprisingly, he alsoestablished that inclusion between chiral host and achiralguest compounds, in which the latter molecules arearranged in a chiral from, could be obtained just bymixing of both components in the solid state. This showsthat achiral molecules move and arrange in a chiral formeasily in the solid state and in the presence of a chiral hostcompound. Mechanisms for all those solid-state reactionswere studied by newly developed monitoring methodsusing IR, UV, CD, AFM, DSC and X-ray techniques. Themechanism established for the solid state reaction is veryuseful to clarify solution reactions. Since these methodsdo not require any organic solvent, the solid statereactions are green, clean, simple, and economic.

The widely varied results of Prof. Toda’s work havebeen published in 350 original papers, 35 reviews, 15books, and 120 patents. He was awarded the SyntheticOrganic Chemistry, Japan Award in 1988, the ChemicalSociety of Japan Award in 1993 and the Inoue HarushigeAward in 1999. He retired from Ehime University in1999 and moved to the Okayama University of Science.We are therefore pleased and honoured to dedicate thisissue on the occasion of his new start in chemistry atOkayama and his 67th birthday. This issue containsarticles from chemists throughout the world who arefriends and colleagues of Prof. Toda. We wish himcontinued success in his career.

Koichi Tanaka

JOURNAL OF PHYSICAL ORGANIC CHEMISTRYJ. Phys. Org. Chem.2000;13: 359

Copyright 2000 John Wiley & Sons, Ltd. J. Phys. Org. Chem.2000;13: 359