1927-71-5Relevant articles and documents
Phosphorylation Organocatalysts Highly Active by Design
Dobrovetsky, Roman,Fallek, Amit,Kramer, Maria,Portnoy, Moshe,Weiss-Shtofman, Mor
supporting information, (2020/05/01)
The activity of nucleophilic organocatalysts for alcohol/phenol phosphorylation was enhanced through attaching oligoether appendages to a benzyl substituent on imidazole- or aminopyridine-based active units, presumably because of stabilizing n-cation interactions of the ethereal oxygens with the positively charged aza-heterocycle in the catalytic intermediates, and was substantially higher than that of known benchmark catalysts for a range of substrates. Density functional theory calculations and the study of analogues having a lower potential for such stabilizing interactions support our hypothesis.
Ligand-free Cu-catalyzed O-arylation of aliphatic diols
Zheng, Yufen,Zou, Wenxing,Luo, Laichun,Chen, Jiabei,Lin, Songwen,Sun, Qi
, p. 66104 - 66108 (2015/08/18)
Coupling reaction between aryl iodides and aliphatic diols was realized with a ligand-free copper catalyst under mild conditions. This method was successfully applied in the process of scale-up synthesis of medicinal candidate product EMB-3.
End-quenching of TiCl4-catalyzed quasiliving polyisobutylene with alkoxybenzenes for direct chain end functionalization
Morgan, David L.,Martinez-Castro, Nemesio,Storey, Robson F.
experimental part, p. 8724 - 8740 (2011/12/02)
Alkoxybenzenes were used to end-quench TiCl4-catalyzed quasiliving isobutylene polymerizations initiated from 2-chloro-2,2,4- trimethylpentane or 5-tert-butyl-1,3-di(1-chloro-1-methylethyl)benzene at -70 °C in 40/60 (v/v) hexane/methyl chloride. The alkoxybenzene/chain end molar ratios were in the range 2.5-4. Effective alkoxybenzene quenchers included those with simple alkyl groups, such as anisole and isopropoxybenzene, haloalkyl tethers, such as (3-bromopropoxy)benzene and (2-chloroethoxy)benzene, and even those with hydroxyl and amine functionality, such as 4-phenoxy-1-butanol and 6-phenoxyhexylamine. Alkylation was generally quantitative and occurred exclusively in the para position; multiple alkylations on the same alkoxybenzene were not observed. The alkylation reactions were tolerant of temperatures ranging from -70 to -30 °C and were unimpeded by the presence of endo- or exo-olefin termini. In situ cleavage of the ether linkage of anisole and isopropoxybenzene termini allowed single pot syntheses of phenol-terminated polyisobutylenes.