Process for the manufacture of furan derivatives

摘要

PCT No. PCT/CH92/00199 Sec. 371 Date Jun. 3, 1993 Sec. 102(e) Date Jun. 3, 1993 PCT Filed Oct. 2, 1992 PCT Pub. No. WO93/07134 PCT Pub. Date Apr. 15, 1993.The invention is concerned with a process for the manufacture of substituted furans which are, in particular, flavorants; thereby 4-hydroxy-2-yn-1-ones or acetals or ketals thereof are cyclized with nucleophilic S-compounds to 3-S-furans, whereby this 3-S atom can be optionally substituted, and the acetylene derivatives, the 4-hydroxy-2-yn-1-ones, can be optionally 1- and/or 4-alkyl or alkenyl substituted.