کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1323712 | 977301 | 2011 | 10 صفحه PDF | دانلود رایگان |
A new range of alkoxy- and alkylsulfanyl-substituted 4,5-dihydro-3H-azepines and 3H-azepines have simultaneously been obtained from conjugated 2-aza-1,3,5-trienes by treatment with t-BuOK under mild reaction conditions (THF/DMSO, ∼−30 °C, 30 min). One-pot synthesis of 1-aza-1,3,4-trienes from α-lithiated alkoxyallenes, isopropyl isothiocyanate and alkyl iodides, followed by the thermally induced sigmatropic [1,5]-H shift, easily leads to starting 2-aza-1,3,5-trienes. The reaction proceeds via generation and [1,7]-electrocyclization of azatrienyl anions and represents a novel simple approach to both azacycloheptadienes and azacycloheptatrienes.
Figure optionsDownload as PowerPoint slideHighlights
► 2-Aza-1,3,5-trienes available from lithiated alkoxyallenes and isothiocyanates.
► Application of t-BuOK for metallation of 2-aza-1,3,5-trienes.
► Simultaneous synthesis of 4,5-dihydro-3H-azepines and 3H-azepines.
Journal: Journal of Organometallic Chemistry - Volume 696, Issue 21, 15 October 2011, Pages 3359–3368