Formation of Chelated Counteranions Using Lewis Acidic Diboranes: Relevance to Isobutene Polymerization
摘要:
The reactions of chelating diboranes with PhCMe2Cl and related initiators were studied by variable-temperature NMR spectroscopy. Although thermally stable ion-pairs featuring weakly coodinating anions (WCA) are formed, isobutene polymerization is complicated by the tendency of these WCA to act as hindered bases toward Bronsted acidic chain ends.
Bifunctional Perfluoroaryl Boranes: Synthesis and Coordination Chemistry with Neutral Lewis Base Donors
作者:Preston A. Chase、Lee D. Henderson、Warren E. Piers、Masood Parvez、William Clegg、Mark R. J. Elsegood
DOI:10.1021/om050764t
日期:2006.1.1
9-borafluorene rings in 2 versus the freely rotating set of pentafluorophenyl rings in 1. The two compounds bind Lewis bases via differing coordination modes, as demonstrated by the solid-state structures of the Lewis base adducts 1·MeCN, 2·THF, and 2·MeCN. Solution studies suggest that bis Lewis base adducts are also accessible; the structures of two examples (1·(MeCN)2 and 2·(THF)2) have been determined
1,2-bis(9-bora-1,2,3,4,5,6,7,8-octafluorofluorenyl)-3,4,5,6-tetrafluorobenzene and related compounds and methods
申请人:Piers Edward Warren
公开号:US20050222463A1
公开(公告)日:2005-10-06
The compound 1,2-bis(9-bora-1,2,3,4,5,6,7,8-octafluorofluorenyl)-3,4,5,6-tetrafluorobenzene, analogs of the compound, and methods for making the compound and its analogs.
Isobutene Polymerization Using Chelating Diboranes: Polymerization in Aqueous Suspension and Hydrocarbon Solution
作者:Stewart P. Lewis、Jianfang Chai、Scott Collins、Timo J. J. Sciarone、Lee D. Henderson、Cheng Fan、Masood Parvez、Warren E. Piers
DOI:10.1021/om8007629
日期:2009.1.12
chelating diboranes o-C6F4[B(C6F5)2]2 (1) and o-C6F4(9-BC12F8)2 (2: 9-BC12F8 = 1,2,3,4,5,6,7,8-octafluoro-9-borafluorene) for the polymerization of isobutene (IB) in aqueous suspension or in hydrocarbonsolution was studied. Polymerizations in aqueous suspension provided polymer of moderate MW and at variable conversion and were dependent on temperature, mode of diborane addition, the presence of surfactant
螯合乙硼烷o -C 6 F 4 [B(C 6 F 5)2 ] 2(1)和o -C 6 F 4(9-BC 12 F 8)2(2:9-BC 12 F 8对于异丁烯(IB)在水悬浮液或烃溶液中的聚合反应,研究了1,2,3,4,5,6,7,8-八氟-9-硼芴)。在水悬浮液中的聚合提供中等分子量和可变转化率的聚合物,并且取决于温度,乙硼烷添加方式,表面活性剂的存在以及水相中阴离子的酸度和性质。研究了在水悬浮液中MW在T范围-80至-20°C时的T依赖性,并且在较低T下形成了较高的MW聚合物。通过NMR光谱研究了乙硼烷1和2的水解和甲醇分解。乙硼烷1的反应用过量的MeOH或水制得含氧鎓酸的溶液[ o -C 6 F 4 B(C 6 F 5)2 } 2(μ-OR)] [(ROH)n H](7:R = H,n > 2; 3:R = Me,n = 3)。当乙硼烷1的含量超过水或MeOH时,观察到乙硼烷的降解。在这种情况下,乘积为o
Formation of Chelated Counteranions Using Lewis Acidic Diboranes: Relevance to Isobutene Polymerization
作者:Jianfang Chai、Stewart P. Lewis、Scott Collins、Timo J. J. Sciarone、Lee D. Henderson、Preston A. Chase、Geoffrey J. Irvine、Warren E. Piers、Mark R. J. Elsegood、William Clegg
DOI:10.1021/om700672q
日期:2007.11.1
The reactions of chelating diboranes with PhCMe2Cl and related initiators were studied by variable-temperature NMR spectroscopy. Although thermally stable ion-pairs featuring weakly coodinating anions (WCA) are formed, isobutene polymerization is complicated by the tendency of these WCA to act as hindered bases toward Bronsted acidic chain ends.