Furan derivatives, useful as fragrances, having the formula ##STR1## wherein R is alkyl or alkenyl and R.sub.1 is alkyl, alkenyl, cycloalkyl, cycloalkenyl or aryl.
Organomanganese (II) reagents XX: Manganese mediated Barbier and Reformatsky like reactions an efficient route to homoallylic alcohols and β-acetoxyesters
作者:Gérard Cahiez、Pierre-Yves Chavant
DOI:10.1016/s0040-4039(00)70700-3
日期:1989.1
Allylic halides and α-bromoesters react with manganese metal in ethyl acetate; THF can also be used as solvent if a catalytic amount of zinc chloride is added to the reaction mixture. When the reaction is performed in the presence of various aldehydes or ketones, excellent yields of 1,2-addition products are obtained in preparative conditions.
Microwave- or Microreactor-Assisted Conversion of Furfuryl Alcohols into 4-Hydroxy-2-cyclopentenones
作者:Oliver Reiser、Kathrin Ulbrich、Peter Kreitmeier
DOI:10.1055/s-0030-1258534
日期:2010.8
The conversion of a variety of furfuryl alcohols, derived from renewable non edible resources such as bran, into 4-hydroxy-2-cyclopentenones was accomplished using microwave irradiation. In subcritical water (220 ËC, 15.5 bar) without the need for any catalyst the reaction proceeds approximately two orders of magnitude faster with up to twice the yield compared to methods previously reported that apply conventional heating techniques. For the parent furfuryl alcohol the process could be transferred to a microreactor, allowing the synthesis of 4-hydroxy-2-cyclopentenone in a continuous flow system on multigram scale.