Treatment of ynol ether-tethered dialkyl acetals with catalytic quantities of scandium triflate in CH(3)CN gives rise to five-, six-, and seven-membered alkoxycycloalkene carboxylates in good to excellent yields. Tri- and tetrasubstituted carbocyclic and heterocyclic alkenes may be formed by this method, and the products obtained may serve as useful intermediates for natural product synthesis.

ion from the solvent by the excited cyclocamphanone to give (XXV), cleavage of the cyclopropane ring to give (XXXVI), and hydrogen atom transfer and ketonization. This postulated route for the isomerization of cyclocamphanone to (XXXIV) is based on the proposal by Srinivasan for the route of isomerization of camphor to the ketone (XIV)'°. The photolysis of (XXXIV) to give (XVI) finds close anal...

Nano-silica supported boron trifluoride (BF3.SiO2) is an efficient, reusable and eco-friendly catalyst for chemoselective thioacetalization of aldehydes and ketones. So, this catalyst was applied for transthioacetalization of acetals and acylals into their corresponding 1,3-dithiolanes or 1,3-dithianes  in good to excellent yields. The reactions were carried out at room temperature under solven...

Nano-silica supported boron trifluoride (BF3.SiO2) is an efficient, reusable and eco-friendly catalyst for chemoselective thioacetalization of aldehydes and ketones. So, this catalyst was applied for transthioacetalization of acetals and acylals into their corresponding 1,3-dithiolanes or 1,3-dithianes  in good to excellent yields. The reactions were carried out at room temperature under solven...

Efficient and chemoselective protection of aldehydes to the corresponding dimethyl acetals have been carried out by mixture of trimethyl orthoformate and methanol in the presence of a catalytic amount of TMSCl or AlCl3 under microwave irradiation. Under these conditions, acetalization of ketones does not take place and they remain intact under reaction conditions. The results are compared with ...