resumo
The utility of BF3-aided lithiation of 4-dimethylaminopyridine (1) with lithium diisopropylamide (LDA) or lithium tetramethylpiperidide (LTMP) in the synthesis of 4-(dimethylaminopyridyl)chalcogenides (Se, Te) has been studied. The lithiation of the in situ generated 4-dimethylaminopyridine-BF3 adduct (2) with LTMP (1.1 eq.) followed by chalcogen insertion and electrophilic quenching reaction afforded the corresponding pyridylchalcogenides in excellent yields. The use of LDA with a modified procedure gave pyridylchalcogenides in yields comparable to that obtained with LTMP. Single crystal X-ray studies of bis(4-dimethylamino-2-pyridyl) diselenide (6), bis(4-dimethylamino-2-pyridylselenenyl) methane (9) and 4-dimethylamino-2,6-bis(methylselenenyl)pyridine (11) have also been reported. The structural analysis reveals a rare cis, trans conformation among the bis(2-pyridyl) diselenides in 6 and pi center dot center dot center dot pi stacking interactions between the pyridine rings in 9. (C) 2013 Elsevier B. V. All rights reserved.
palavras-chave
PYRIDYLSELENO GROUP; SELENIUM-COMPOUNDS; CRYSTAL-STRUCTURE; COMPLEXES
categoria
Chemistry
autores
Dhau, JS; Dhir, R; Singh, A; Brandao, P; Felix, V
nossos autores
Paula Cristina Ferreira da Silva Brandão
Investigador Auxiliar
Vítor Félix
Professor Associado com AgregaçãoGrupos
1 - nanomateriais inorgânicos funcionais e híbridos orgânico-inorgânico
6 - simulação computacional e modelação multi-escala
agradecimentos
We are thankful to the CSIR, New Delhi, India, for financial support. Additional support from SAP by UGC, New Delhi, is also acknowledged.