Sehr starke Organosuperbasen durch Verknüpfung von Imidazol‐ und Guanidinbasen – Synthese, Struktur und Basizität

Neue Strukturmotive fur Organosuperbasen, die leicht zuganglich sind und hohe Basizitaten aufweisen, sind fur viele Bereiche der Chemie dringend notwendig. Wir berichten hier uber die Synthese von N,N′-Bis(imidazolyl)guanidin-Basen (BIG-Basen). Ihre pKα-Werte wurden zu 26.1–29.3 in THF bestimmt. Sie sind damit wahrscheinlich die starksten phosphorfreien organischen Basen sowohl in Losung als auch in der Gasphase. Rechnungen halfen bei der Bestimmung der strukturellen und elektronischen Faktoren, die zur beobachteten hohen Basizitat beitragen.

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