Bifunctional catalytic surface enables significant acceleration of organic reactions by concerted catalysis. For example, allylation of nucleophiles smoothly occurred on a SiO₂ surface possessing both Pd complex and tertiary amine. In the case of the catalysts with Pd-bisphosphine complex and 1,4-diazabicyclo [2.2.2] octane (DABCO) on same SiO₂ surface, the turnover number (TON) value based on Pd species approached up to 106000. Other reaction systems containing Rh complex and In cation for 1,4-addition of organoboronic acid and cyanation reaction of aldehyde, respectively, are also described. These SiO₂- and SiO₂-Al₂O₃-supported catalysts were characterized by several spectroscopic techniques, such as solid-state NMR, X-ray absorption fine structure (XAFS) spectroscopy, and X-ray photoelectron spectroscopy (XPS), for atomic or molecular-level understanding. Reaction mechanisms including acceleration process is also discussed based on several experiments.

Catalytic hypervalent iodine oxidation reactions of phenols and alcohols with iodoarene-Oxone^® system were developed. Oxone^® (2KHSO₅·KHSO₄·K₂SO₄) is well known as a safe and inexpensive oxidant. 4-Iodophenoxyacetic acid (IPAA) is efficient for the phenol oxidations. IPAA is commercially available and it is so soluble with a weak alkaline solution, such as saturated sodium bicarbonate solution, that it is easy separable from the product. 2-Iodobenzamide (IBamide) is efficient for the alcohol oxidations. The oxidation reaction using IBamide with Oxone^® can be carried out at room temperature. The catalytic activity of IBamide is lower than that of 2-iodobenzoic acid at 70 °C, whereas higher at room temperature.

In this review article, we cast doubt on true necessity of complicated organic synthesis for development of functional materials. Instead of synthesizing many molecules, one particular molecule may exhibit varieties of functions just through selecting appropriate environment and its dynamic structural changes. For example, molecular recognition capabilities can be significantly enhanced by placing the molecules at appropriate interfacial environments. Binding constants between phosphate and guanidinium are enhanced by 100-10000 times simply by shifting media from dispersed solution to mesoscopic interfaces of micelles and vesicles. The corresponding constants are further enlarged by 1000000-10000000 times at macroscopic interfaces such as the air-water interfaces. This surprising fact is proved both by experimental and theoretical approaches. Mechanical deformation of particular molecules at interfacial environments makes it possible to freely tune recognition of chiral amino acids and highly enhance discrimination of very similar substances, thymine and uracil derivatives. Further more, such mechanical process at interfaces enable us to operate molecular machines by hand-motion-like macroscopic stimuli. These examples demonstrated that medium-selection and molecular deformations can result in modification and tuning of molecular functions incredibly and could make impossible functions really possible. Now we have to think about aggressive introductions of surface science concepts and supramolecular essences to traditional organic syntheses for further developments of functional molecular sciences.

Nonequilibrium-to-equilibrium chemical reactions, involving change of a metastable to an equilibrium state, are discussed from the aspects of reaction paths and thermodynamics. Such reaction exhibits multiple-paths nature in microscopic molecular structural changes and in macroscopic molecular concentration changes. Involvement of reversibility largely enhances the multiple-paths nature. We describe here our recent studies on the reversible nonequilibrium molecular switching system of sulfonamidohelicene oligomer in diluted solution, which involves the reversible nonequilibrium-to-equilibrium chemical reactions. Molecular structural changes from metastable random-coil to helix-dimer under equilibrium with self-catalysis show notable chemical phenomena of molecular thermal hysteresis, molecular memory effect, threshold phenomena, counting the numbers 1 and 2, and concentration amplification.

Magnesium is one of the most familiar elements. However, magnesium may only remind organic chemists of Grignard reaction. Some chemists will add pinacol coupling and what type of reactions will you say in relation with magnesium? Magnesium has many benefits such as eco-friendly, reactive, stored in the air, cheap, etc. We used this material as an electron transfer reagent for organic reactions and reported reductive coupling reactions with new combination of reagents. Electron-deficient carbons such as carbonyl carbons and the β-carbon of conjugated carbonyl compounds reacted with electrophiles to form carbon-carbon bonds and carbon-silicon bonds through umpolung by magnesium-promoted reduction. In this article, new development of magnesium-promoted coupling reactions will be reported in detail, especially, application of silylation to non-benzenoid aromatic compounds, synthesis of multi-functionalized allenes, reductive carboxylation, novel synthesis of fluorine-containing compounds by trifluoroacetylation, abnormal introduction of a trifluoroacetyl group to aromatic rings, and silylation and trifluoroacetylation of vinylpyridines.

Polyoxygenated steroids cardenolides, typified by ouabagenin, possess a broad spectrum of biological activity such as inotropic activity. Due to their unique structure, including unusual cis-fused A/B- and C/D ring junction, and a number of β-configured oxygenated functional group, they have been an attractive target in chemical synthesis. In this review, recent developments in the practical synthetic strategies toward these cardenolides are described.

Photoredox catalysts are powerful and attractive tools in organic synthesis. They enable the construction of various bonds and activation of low reactive substrates by single-electron transfer. Over the past few years, some challenging reactions have been accomplished by using photoredox catalysts. Especially, many cross-coupling reactions of various substrates using photoredox catalysts have been reported. This review highlights decarboxylative cross-coupling reaction of abundant and inexpensive amino acids using photoredox catalysts.

Phorbol, a diterpene isolated in 1934 from hydrolysis products of croton oil, exhibits immunoregulatory, antiviral, and anticancer activities, and has a highly oxygenated tigliane skeleton that is too difficult to synthesize. In past studies, Wender and Cha groups reported the total synthesis of phorbol, but the syntheses require many steps (40∼52 steps). In 2016, Baran group achieved the enantioselective total synthesis of (+)-phorbol in only 19 steps from commercially available (+)-3-carene by using a concept of innovative strategy “two-phase terpene synthesis”.