close

Вход

Забыли?

вход по аккаунту

?

код для вставки
2004
Cyclobutane derivatives
Q 0022
Highly Functionalized Cyclobutanols by Samarium(II) Iodide Induced Radical
of Carbohydrate-Derived Unsaturated Ketones. — The cyclization of
45- 076 Cyclizations
ketones (I) affords diastereomeric mixtures of cis products. The diastereoselectivity is
found to be dependent on the protecting group R. While the Tbs-protected ketone (Ia)
affords a 2:1 ratio of diastereomers, the trityl analogue (Ib) gives diastereomers (II) and
(III) in a 4:1 ratio, along with trace amounts of a third trans diastereomer. The pivaloyl-protected analogue of ketones (I) fails to undergo cyclization. Instead, reductive elimination occurs. Cyclobutane (IIb) is converted into an intermediate (IV) for the synthesis of a nucleoside anti-viral analogue. — (WILLIAMS*, D. B. G.; BLANN, K.; Eur.
J. Org. Chem. 2004, 15, 3286-3291; Dep. Chem. Biochem., Rand Afrikaans Univ.,
Auckland Park, Johannesburg 2006, S. Afr.; Eng.) — Klein
Документ
Категория
Без категории
Просмотров
0
Размер файла
20 Кб
Теги
1/--страниц
Пожаловаться на содержимое документа