Pyridiniumgeminisurfactants with hexadecyl chains linked to nitrogen atoms and a tuned aliphatic spacer that bridges the two pyridinium polar heads in 2,2'-positions have been synthesized and characterized. A multitechnique approach allowed us to study the aggregation behavior, using conductivity, surface tension, and fluorescence. Graphs of the specific conductivity (κ) versus the surfactant molar
Electroreductive coupling of vinylpyridines and vinylquinolines: radical anion–substrate cycloaddition?
作者:Robert G. Janssen、Majid Motevalli
DOI:10.1039/a707460c
日期:——
Cathodic reduction of 2- and 4-vinylpyridine and of 2-vinylquinoline gives trans-1,12-di(heteroaryl)cyclobutanes as major products; they arise via radical anionâsubstrate cycloaddition.
A series of fluorinated geminipyridinium amphiphiles have been prepared, purified and fully characterized. The synthesis was performed using alkyl trifluoromethanesulfonates as the quaternizing agents, provided very good yields and overcame problems arising with other less powerful alkylating agents. The use of different characterization techniques, such as conductivity and surface tension measurements
Taming Highly Unstable Radical Anions and 1,4-Organodilithiums by Flow Microreactors: Controlled Reductive Dimerization of Styrenes
作者:Yiyuan Jiang、Hideki Yorimitsu
DOI:10.1021/jacsau.2c00375
日期:2022.11.28
dimerization, and the resulting 1,4-organodilithiums are trapped with various electrophiles. Trapping with divalent electrophiles affords precursors for useful yet less accessible cyclic structures, for example, siloles from dichlorosilanes. Thus, we highlight the power of single-electron reduction of unsaturated compounds in flowmicroreactors for organic synthesis.
Copper deposition in wafer level packaging of integrated circuits
申请人:MacDermid Enthone Inc.
公开号:US11124888B2
公开(公告)日:2021-09-21
An electrodeposition composition comprising: (a) a source of copper ions; (b) an acid; (c) a suppressor, and (d) a leveler, wherein the leveler comprises a quaternized dipyridyl compound prepared by reacting a dipyridyl compound with a difunctional alkylating agent or a quaternized poly(epihalohydrin). The electrodeposition composition can be used in a process for forming a copper feature over a semiconductor substrate in wafer level packaging to electrodeposit a copper bump or pillar on an underbump structure of a semiconductor assembly.