Bis(aldehydes): Versatile precursors for novel bis(14H‐dibenzo[a,j]xanthenes), bis(pyrano[3,2‐c:5,6‐c']dichromenedione), and bis(dihydrobenzo[a]xanthenones) via multicomponent reactions

Abstract

A synthesis of novel bis(4‐(14H‐dibenzo[a,j]xanthenes) and bis(dihydro‐8H‐benzo[a]xanthenones) was performed in good yields via pseudo‐multicomponent, or multicomponent reactions, of bis‐aldehydes with four equivalents of β‐naphthol or with a mixture of two equivalents of each β‐naphthol and dimedone in the presence of a catalytic amount of p‐toluenesulfonic acid. Bis(pyrano[3,2‐c:5,6‐c′]dichromenediones) or tetrakis(4‐hydroxy‐2H‐chromen‐2‐ones) could also be obtained in good yields through pseudo‐multicomponent reactions of bis(aldehydes) with four molar ratio of 4‐hydroxycoumarin.

Pseudo-multicomponent reactions

“…In 2021, Abdelhamid and Elwahy 101 achieved the synthesis of novel bis(14 H -dibenzo[ a , j ]xanthenes), bis(pyrano[3,2- c :5,6- c ′]dichromenedione) and bis(dihydrobenzo[ a ]-xanthenones) using p -toluenesulfonic acid as catalyst. The repetitive pseudo-5CR involved bis-aldehydes 652a–d and two equivalents of β-alcohols 653a–c.…”

MOFs impregnados con agua y otros disolventes para evaluar sus propiedades en la captura selectiva de gases de efecto invernadero y reacciones pseudo-multicomponentes

“…Esquema 35. Mecanismo de reacción sugerido para a síntesis de bis[2-(arilimino)-1,3-tiazolidin-4onas].En 2021, Abdelhamid y Elwahy[194] reportaron la síntesis de nuevos bis(14Hdibenzo[a,j]xantenos), bis(pirano[3,2-c:5,6-c']dicromenediona) y bis(dihidrobenzo[a]xantenonas usando ácido p-toluenosulfónico como catalizador. Los reactivos utilizados son bis-aldehídos 267, β-alcoholes 268.…”