33CHLOROO33METHYLLBUTANEE OR 33METHYLL22BUTENEE1*44DIARYLLBISACETAL AND ITS MANUFACTURE

摘要

3-Chloro-3-methyl-butane-1,4-dial-bis-acetals and 3-methyl-but-2-ene-1,4-dial-bis-acetals are obtained by reacting a six-membered cyclic acetal of 3-methyl-but-3-en-1-al with an alkyl nitrite in the presence of methanol and hydrogen chloride and, if desired, eliminating HCl in the conventional manner. The butanedial-bis-acetals and butenedial-bis-acetals are valuable intermediates through which the trans-3-methyl-but-2-ene-1,4-dial-1-acetals, which are sought-after products for terpene syntheses, can be obtained in an industrially particularly advantageous manner.