Steric Effects in Elimination Reactions. II. The Effect of the Steric Requirements of Alkyl Substituents upon the Extent and Direction of Unimolecular Elimination in the Solvolysis of Tertiary Alkyl Bromides
The photobromination of CHbonds by using molecular bromine was reinvestigated under microfluidic conditions. The continuous‐flow method suppressed the production of dibrominated compounds and effectively produced the desired monobrominated products with high selectivity. Rapid bromination of benzylic substrates containing a photoaffinity azide group was achieved without any decomposition.
Process for the preparation of dimethylketene and then of polydimethylketene fro isobutyric anhydride
申请人:Hub Serge
公开号:US20060270878A1
公开(公告)日:2006-11-30
The present invention relates to a process for the preparation of dimethylketene (DMK) and then of polydimethylketene (PDMK) by polymerization of DMK. More specifically, the DMK is obtained by pyrolysis by isobutyric anhydride (IBAN), the latter decomposing under the effect of heat (pyrolysis) to give isobutyric acid (IBA) and DMK. One mole of pyrolyzed IBAN gives one mole of IBA and one mole of DMK.
Nucleophilic Solvent Participation in the Solvolysis of Tertiary Bromoalkanes
作者:Kwang-Ting Liu、Su-Jiun Hou、Meng-Lin Tsao
DOI:10.1002/jccs.200900063
日期:2009.4
indicated limiting SN1 mechanism for the solvolysis. On the other hand, bromides 1B‐6B and 8B gave linear correlations (R = 0.987–0.996) with the dual‐parameter (YBr and NOTs) equation (2) only, which indicated the presence of significant nucleophilic solvent participation. Normal trends of reactivity due to the relief of B‐strain could be found in the poorly nucleophilic trifluoroethanol. Similar to the corresponding
The invention provides for polymerization processes to produce polymers utilizing boiling pool reactor systems and diluents including hydrofluorocarbons.
本发明提供了利用沸腾池反应器系统和包括氢氟碳化物的稀释剂进行聚合过程以生产聚合物的方法。
Polymers with new sequence distributions
申请人:Shaffer Daniel Timothy
公开号:US20060100409A1
公开(公告)日:2006-05-11
The invention relates to new polymerization processes including diluents including hydrofluorocarbons and their use to produce novel polymers with new sequence distributions. In particular, the invention relates to copolymers of an isoolefin, preferably isobutylene, and a multiolefin, preferably a conjugated diene, more preferably isoprene, with new sequence distributions.