Synthesis and Reactivities of 1,5- and 1,7-Azulenequinone Derivatives. A Highly Convenient, One-Pot Synthesis of 3-Bromo-1,5- and −1,7-Azulenequinones by Bromination of Azulene,
摘要:
AbstractA very convenient, one‐pot synthesis (over 80% yield) of 3‐bromo‐1,5‐ and −1,7‐azulenequinones has been developed by bromination of azulene in aqueous tetrahydrofuran. Reduction of 3‐bromo‐1,5‐ and −1,7‐azulenequinones with tin or zinc powder in acetic acid gave the parent 1,5‐ and 1,7‐azulenequinones, and further reduction products.
Synthesis and Reactivities of 1,5- and 1,7-Azulenequinone Derivatives. A Highly Convenient, One-Pot Synthesis of 3-Bromo-1,5- and −1,7-Azulenequinones by Bromination of Azulene,
摘要:
AbstractA very convenient, one‐pot synthesis (over 80% yield) of 3‐bromo‐1,5‐ and −1,7‐azulenequinones has been developed by bromination of azulene in aqueous tetrahydrofuran. Reduction of 3‐bromo‐1,5‐ and −1,7‐azulenequinones with tin or zinc powder in acetic acid gave the parent 1,5‐ and 1,7‐azulenequinones, and further reduction products.
3-Bromo derivatives of 1,5- and 1,7-azulenequinones easily react with various nucleophiles to give 3-methoxy, phenoxy, p-nitrophenoxy, butylthio, butylamino, p-tolylamino, dimethylamino, 2-hydroxyethylamino, azulenyl, and guaiazulenyl derivatives of the respective azulenequinones almost quantitatively. 3-Bromo-1,5- and -1,7-azulenequinones afford the 2,3-bisbutylthio derivatives under basic conditions