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Synthesis of bis(indolyl)methanes Catalyzed by Triethylborane
J Pablo García Merinos1, Heraclio López Ruíz2, Yliana López3
1Área Académica de Química, Universidad Autónoma del Estado de Hidalgo, Carretera Pachuca- Tulancingo Km. 4.5, Mineral de La Reforma, Hidalgo, CP 42076, Mexico, ; bInstituto de Investigaciones Químico-Biológicas, Universidad Michoacana de San Nicolás de Hidalgo, Ed.B-1, C.U., Morelia, Michoacán, 58030, México.
Abstract:
Triethylborane (TEB) was found to be a mild, efficient, and acid catalyst in electrophilic substitution reaction of indoles with aldehydes compounds to afford the corresponding bis(indolyl)methanes. Vibrindole A (5) and bis(indolyl)methanes derivatives 16 and 18 were synthesized using this methodology. Compound 16 is an intermediary in the synthesis of the natural bisindoles arsindoline B (2) and streptindole (6). The structure of vibrindole A (5) was unequivocally confirmed by a single crystal X-ray diffraction analysis.
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