磷-迈克尔加成反应是磷基亲核试剂与受体取代的不饱和键的加成反应,它无疑是形成PC键的最通用,最强大的工具之一,因为可以使用许多不同的亲电试剂和P亲核试剂。彼此结合。这提供了访问许多功能多样的产品的可能性。在这项工作中,使用了两种基于吡啶的碱性有机催化剂有效地催化磷-迈克尔加成反应:4- N,N-二甲基氨基吡啶糖精盐(DMAP·Hsac)盐和氟长链吡啶(4- R f -CH 2 OCH 2 -py,其中R f = C11楼23)。这些催化剂已经合成并且由Lu's基团表征。在这些催化剂存在下,亚磷酸二异丙酯,亚甲基二甲基或三乙基亚磷酸酯在α,β-不饱和丙二酸酯中的磷-迈克尔加成反应显示出非常好的反应性,在80-100°C下可在1-4.5 h内获得高收率,并具有高催化回收率和可重复使用性。关于显着的催化剂回收,有时通过使用非极性溶剂(例如醚)使催化剂析出,DMAP·Hsac加合物有时观察到超过八
RECYCLABLE CATALYSTS FOR ESTERIFICATION OR ACYLATION OF ALCOHOLS
申请人:LU NORMAN
公开号:US20120184748A1
公开(公告)日:2012-07-19
A compound is useful as a recyclable catalyst for esterification or acylation of alcohols and consists of saccharine and a compound comprising a pyridine moiety. In addition, also a method of preparing the compound and an ester synthesis method using the compound are introduced.
Pyridinium saccharinate salts as efficient recyclable acylation catalyst: a new bridge between heterogeneous and homogeneous catalysis
作者:Norman Lu、Wei-Hsuan Chang、Rong-Jyun Wei、Yung-Cheng Fang、Tu-Wen Han、Guo-Quan Wang、Jia-Yaw Chang、Yuh-Sheng Wen、Ling-Kang Liu
DOI:10.1016/j.tet.2016.04.073
日期:2016.6
The homogeneous nature of DMAP-catalyzed acylation still suffers from the problems of catalyst separation and/or residual DMAP contamination. DMAP causes acute dermal toxicity, whereas the corresponding DMAP salt exhibits only slight irritation to the skin. Very recently, we found that the DMAP saccharinate salt is also great recyclablecatalyst, whose acylation of alcohols has been successfully and effectively
l‐lactide (LLA) and δ‐valerolactone (VL) with benzyl alcohol (BnOH) as an initiator. The bifunctional DMAP ⋅ Sac coordinated to living polymer chain‐end with enolate oxygen to hydrogen of the hydroxyl, and to monomer with pyridinium N−H to oxygen of the carbonyl that successfully catalyzed efficient polymerization of LLA. High relative growth rate (RGR>90%) of the DMAP ⋅ Sac containing poly(l‐lactic acid) (PLLA)
Disclosed in the present invention is a preparation method for a polyester, relating to the technical field of organic catalysis and polymeric materials. The preparation method in the present invention comprises: (1) using pyridine and saccharin in a ratio of 1:1 to prepare pyridine saccharin salt in tetrahydrofuran at 60° C. and separating the pyridine saccharin salt out in methanol and hexane. (2) Freeing out a small amount of pyridine from the pyridine saccharin salt in a heating state, catalyzing by the pyridine saccharin salt and pyridine a cyclic lactone or a carbonate to be ring-opened and polymerized to form the polyester; and the system has no other compound residues. (3) In the presence of an alcohol initiator, catalyzing by the pyridine saccharin salt the cyclic lactone to be ring-opened and polymerized to obtain the polyester. The catalytic system can efficiently synthesize a specific polylactone. Compared with a method for synthesizing a polyester by the use of a metal-containing catalyst in the prior art, the system has wide application. Moreover, the system is advantageous of no metal residue, narrow molecular weight distribution and no chain transesterification, and therefore has great commercial application potential in bio-pharmaceutical field and microelectronic field.
本发明公开了一种聚酯的制备方法,涉及有机催化和高分子材料技术领域。本发明的制备方法包括:(1) 使用吡啶和糖精以 1:1 的比例在 60° C 的四氢呋喃中制备吡啶糖精盐,并在甲醇和己烷中分离出吡啶糖精盐。(2) 在加热状态下从吡啶糖精盐中游离出少量吡啶,通过吡啶糖精盐和吡啶催化环状内酯或碳酸酯开环聚合形成聚酯;且体系中无其他化合物残留。(3) 在醇类引发剂存在下,通过吡啶糖精盐催化环状内酯开环聚合,得到聚酯。该催化系统可高效合成特定的聚内酯。与现有技术中使用含金属催化剂合成聚酯的方法相比,该系统具有广泛的应用前景。此外,该体系还具有无金属残留、分子量分布窄、无链转移等优点,因此在生物制药领域和微电子领域具有巨大的商业应用潜力。