申请人:Roche Vitamins Inc.
公开号:US05817838A1
公开(公告)日:1998-10-06
A process for the manufacture of 4,4-disubstituted 5-methylene-1,3-dioxolan-2-ones ("cyclocarbonates") of the formula: ##STR1## wherein R.sup.1 and R.sup.2 each independently signify a saturated or olefinically-unsaturated aliphatic group or an aromatic group, or R.sup.1 and R.sup.2 together form tetra- or pentamethylene, by reacting a corresponding 3,3-disubstituted prop-1-yn-3-ol of the formula HC.tbd.C--C(R.sup.1)(R.sup.2)--OH (II) with carbon dioxide in the presence of a quaternary ammonium or phosphonium salt as the catalyst comprises using a silver salt as a further catalyst. An alkali metal or quaternary ammonium or phosphonium salt of a carboxylic acid can also be used to increase the catalytic performance of the silver salt catalyst. Moreover, the addition of triphenylphosphine serves to accelerate the reaction to some extent. The silver salts catalyze this process significantly better than the previously utilized copper salts. Advantageously, the process uses much smaller amounts of catalyst, significantly shortens reaction times, and mandates less drastic reaction conditions. Cyclocarbonates produced by this process are valuable intermediates for the production of polymerizates and other useful substances, such as dyestuffs and carotenoids.
一种制备4,4-二取代5-亚甲基-1,3-二氧杂环己烷-2-酮(“环碳酸酯”)的工艺,化学式如下:其中R^1和R^2各自独立表示饱和或烯烃不饱和的脂肪基或芳香基,或者R^1和R^2共同形成四元或五元亚甲基,通过将相应的化学式为HC.tbd.C--C(R^1)(R^2)--OH(II)的3,3-二取代丙-1-炔-3-醇与二氧化碳在季铵盐或膦盐存在下反应而制备,包括使用银盐作为进一步的催化剂。碱金属或羧酸的季铵盐或膦盐也可用于提高银盐催化剂的催化性能。此外,三苯基膦的添加在一定程度上加速了反应。银盐催化这一过程比以前使用的铜盐显著更好。该工艺使用催化剂量较小,显著缩短了反应时间,并且要求的反应条件较不严苛。通过该工艺生产的环碳酸酯是用于生产聚合物和其他有用物质(如染料和类胡萝卜素)的有价值的中间体。