18819-89-1Relevant articles and documents
SN2 Reactions in Hydrocarbon Solvents Using Ammonium-Terminated Polyisobutylene Oligomers as Phase-Solubilizing Agents and Catalysts
Samunual, Peerada,Bergbreiter, David E.
, p. 11101 - 11107 (2018)
Although SN2 reactions have been thoroughly studied in polar aprotic and protic solvents, not many studies have been done to study the rate of SN2 reaction in nonpolar solvents like alkanes due to the insolubility of anionic nucleophiles in these solvents. In this study, we investigated the use of N,N-diethyl-N-methylammonium-terminated polyisobutylene oligomers as phase-solubilizing agents for nucleophilic anions that could react with hydrocarbon-soluble substrates in alkanes. The results of these kinetic studies showed alkanes were comparable to MeCN as solvents in many reactions. Based on these studies, we developed a solid/liquid catalytic process using insoluble alkali metal carboxylate salts and a recyclable soluble polyisobutylene-bound catalyst that can be used to carry out SN2 reactions both in heptane and in hydrocarbon oligomeric solvents known as poly(α-olefins) (PAOs).
Superfast and Water-Insensitive Polymerization on α-Amino Acid N-Carboxyanhydrides to Prepare Polypeptides Using Tetraalkylammonium Carboxylate as the Initiator
Chen, Jiacheng,Chen, Kang,Ding, Yun,Ji, Zhemin,Liu, Longqiang,Liu, Runhui,Liu, Shiqi,Shao, Ning,Wu, Xue,Wu, Yueming,Zhang, Weiwei,Zhou, Min,Zhu, Minghui
supporting information, p. 26063 - 26071 (2021/11/12)
We design the tetraalkylammonium carboxylate-initiated superfast polymerization on α-amino acid N-carboxyanhydrides (NCA) for efficient synthesis of polypeptides. Carboxylates, as a new class of initiator for NCA polymerization, can initiate the superfast NCA polymerization without the need of extra catalysts and the polymerization can be operated in open vessels at ambient condition without the use of glove box. Tetraalkylammonium carboxylate-initiated polymerization on NCA easily affords block copolymers with at least 15 blocks. Moreover, this method avoids tedious purification steps and enables direct polymerization on crude NCAs in aqueous environments to prepare polypeptides and one-pot synthesis of polypeptide nanoparticles. These advantages and the mild polymerization condition of tetraalkylammonium carboxylate-initiated NCA polymerization imply its great potential in functional exploration and application of polypeptides.
Development and Elucidation of a Pd-Based Cyclization–Oxygenation Sequence for Natural Product Synthesis
Yi, Heng,Hu, Pengfei,Snyder, Scott A.
supporting information, p. 2674 - 2678 (2020/01/24)
Pd-catalyzed sequences involving oxidative addition, cyclization, and termination through intermolecular nucleophile capture have tremendous utility. Indeed, they can generate a plethora of different polycyclic structures possessing a diverse range of fun