Aldehydes and ketones are readily protected in the presence of trialkyl orthoformate and a catalytic amount of cerium(III) trifluoromethanesulfonate under mild conditions to give the corresponding acetals in good to excellent yields. Due to the mild reaction conditions, this method is compatible with acid-sensitive substrates.

Bismuth(III) trifluoromethanesulfonate tetrahydrate is found to efficiently catalyze the cyclotrimerization of acetophenones into 1,3,5-triarylbenzenes in good yields.

Polyphenyl derivatives Q 0700 Efficient Conversion of Acetophenones into 1,3,5-Triarylbenzenes Catalyzed by Bismuth(III) Trifluoromethanesulfonate Tetrahydrate. -The method allows the preparation of ortho-substituted target compounds such as (IV). -(ONO, F.; ISHIKURA, Y.; TADA, Y.; ENDO, M.; SATO*, T.; Synlett 2008, 15, 2365-2367; Dep. Life Sci., Kurashiki Univ. Sci. Arts, Kurashiki 712-850, Japan; Eng.) -Mais 04-073

Protection O 0345 A Facile Procedure for Acetalization of Aldehydes and Ketones Catalyzed by Cerium(III) Trifluoromethanesulfonate. -(ONO, F.; INATOMI, Y.; TADA, Y.; MORI, M.; SATO*, T.; Chem. Lett. 38 (2009) 1, 96-97; Dep. Life Sci., Kurashiki Univ. Sci. Arts, Kurashiki, Okayama 712, Japan; Eng.) -H. Toeppel 23-056