close

Вход

Забыли?

вход по аккаунту

?

код для вставки
2005
Fused pyridine derivatives
R 0450
Tetronamides as Latent Acyclic Vinylogous Amides in Formal Aza-[3 + 3]
Reactions with α,β-Unsaturated Iminium Salts. An Unexpected
06- 144 Cycloaddition
Rearrangement and an Approach to Synthesis of Substituted Piperidines. — It is
found that the temperature strongly affects the outcome of the [3 + 3] cycloadditions.
When it is less than 130 °C, the expected cycloadducts of type (III) and (VIII) are mainly formed, while at 150 < t < 220 °C, considerable amounts of head-to tail regioisomers
like (IV) and (IX) are isolated. The latter were found in previous studies. At higher temperature 220 °C, rearrangement of the expected cycloadducts to pyridine derivatives of
type (V) or (XII) takes place. The cycloaddition proceeds without stereoselectivity and
the products can smoothly be transformed into substituted piperidines. —
(SYDORENKO, N.; HSUNG*, R. P.; DARWISH, O. S.; HAHN, J. M.; LIU, J.; J.
Org. Chem. 69 (2004) 20, 6732-6738; Dep. Chem., Univ. Minn., Minneapolis,
MN 55455, USA; Eng.) — Jannicke
2005
Документ
Категория
Без категории
Просмотров
0
Размер файла
50 Кб
Теги
1/--страниц
Пожаловаться на содержимое документа