Multicomponent reactions (MCRs) are fundamentally different from two-component reactions in several aspects. Among the MCRs, those with isocyanides have developed into popular organic-chemical reactions in the pharmaceutical industry for the preparation of compound libraries of low-molecular druglike compounds. With a small set of starting materials, very large libraries can be built up within a short time, which can then be used for research on medicinal substances. Due to the intensive research of the last few years, many new backbone types have become accessible. MCRs are also increasingly being employed in the total synthesis of natural products. MCRs and especially MCRs with isocyanides offer many opportunities to attain new reactions and basic structures. However, this requires that the chemist learns the “language” of MCRs, something that this review wishes to stimulate.

Multicomponent Reactions with Isocyanides.

Low band gap (Eg < 1.5 eV) polycyclic hydrocarbons have become one of the most important types of materials for many applications, for example, as semiconductors in organic field effect transistors (OFETs), as light-harvesting dyes in organic solar cells and photodetectors, as near infrared (NIR) fluorescent probes in high resolution bio-imaging and bio-sensing, and as chromophores in non-linear optics. The benzenoid polycyclic hydrocarbons as nano-sized graphene fragments also serve as perfect model compounds to understand the fundamental structure–property relationship of graphene. The ground state of these molecules can be described as either a closed-shell or an open-shell structure on the basis of their molecular size and edge structure. In this review, a summary will be given on a series of low band gap polycyclic hydrocarbons about their synthesis, physical properties and material applications.

Low band gap polycyclic hydrocarbons: from closed-shell near infrared dyes and semiconductors to open-shell radicals

Multikomponentenreaktionen (MCRs) unterscheiden sich in mehreren Aspekten grundlegend von Zweikomponentenreaktionen. Unter den MCRs haben sich solche mit Isocyaniden in der pharmazeutischen Industrie zu popularen organisch-chemischen Reaktionen zur Herstellung von Substanzbibliotheken aus niedermolekularen wirkstoffartigen Verbindungen entwickelt. Mit einem kleinen Set von Ausgangsverbindungen konnen in kurzer Zeit sehr grose Bibliotheken aufgebaut und fur Fragestellungen in der Wirkstoff-Forschung verwendet werden. Aufgrund der intensiven Forschung der letzten Jahre sind viele neue Strukturtypen zuganglich geworden. Vermehrt werden MCRs auch in der Totalsynthese von Naturstoffen eingesetzt. MCRs und insbesondere MCRs mit Isocyaniden bieten viele Moglichkeiten, zu neuen Reaktionen und Grundgerusten zu gelangen. Dies setzt jedoch voraus, dass der Chemiker die „Sprache“ der MCRs lernt, wozu dieser Ubersichtsartikel anregen soll.

Multikomponentenreaktionen mit Isocyaniden

TDDFT-calculations of Vis/NIR absorbing compounds

Cyclopropenylium cations, cyclopropenones, and heteroanalogues-recent advances.

Tris(thioxanthen-9-ylidene)cyclopropane, and Its Radical Cation and Dication†

Le compose du titre est prepare par reaction du derive lithie du thioxanthene avec le perchlorocyclopropane

Tris(thioxanthen-9-yliden)cyclopropan sowie dessen Radikalkation und Dikation†

Redox‐Active Thieno[3,2‐b]thiophene as a Novel, Three‐Color Electrochromic System

Par dimerisation de la bis-[di-t-butyl-3,5 hydroxy-4 phenyl] (=bis-R) cyclopropenethione, synthese de tetrakis-R thieno [3,2-b] thiophene; oxydation de 2 ou des 4 substituants en di-«t»-butyl-3,5 oxo-4 cyclohexadiene-2,5ylidene

Toshio Nagatomi

Papers

Tris(thioxanthen-9-ylidene)cyclopropane, and Its Radical Cation and Dication†

Tris(thioxanthen-9-yliden)cyclopropan sowie dessen Radikalkation und Dikation†

Redox‐Active Thieno[3,2‐b]thiophene as a Novel, Three‐Color Electrochromic System

Ein redoxaktives Thieno[3,2-b]thiophen als neues, dreifarbiges elektrochromes System

Synthesis of pyrroline via cyclization of 4-isocyano-1-siloxy-1-alkene induced by an iminium salt