17844-23-4Relevant articles and documents
Regio- and Diastereoselective Iron-Catalyzed [4+4]-Cycloaddition of 1,3-Dienes
Kennedy, C. Rose,Zhong, Hongyu,MacAulay, Rachel L.,Chirik, Paul J.
supporting information, p. 8557 - 8573 (2019/06/04)
A family of single-component iron precatalysts for the [4+4]-cyclodimerization and intermolecular cross-[4+4]-cycloaddition of monosubstituted 1,3-dienes is described. Cyclooctadiene products were obtained with high regioselectivity, and catalyst-controlled access to either cis- or trans-diastereomers was achieved using 4-substituted diene substrates. Reactions conducted either with single-component precatalysts or with iron dihalide complexes activated in situ proved compatible with common organic functional groups and were applied on multigram scale (up to >100 g). Catalytically relevant, S = 1 iron complexes bearing 2-(imino)pyridine ligands, (RPI)FeL2 (RPI = [2-(2,6-R2-C6H3-Na-CMe)-C5H4N] where R = iPr or Me, L2 = bis-olefin), were characterized by single-crystal X-ray diffraction, M??bauer spectroscopy, magnetic measurements, and DFT calculations. The structural and spectroscopic parameters are consistent with an electronic structure description comprised of a high spin iron(I) center (SFe = 3/2) engaged in antiferromagnetically coupling with a ligand radical anion (SPI = -1/2). Mechanistic studies conducted with these single-component precatalysts, including kinetic analyses, 12C/13C isotope effect measurements, and in situ M??bauer spectroscopy, support a mechanism involving oxidative cyclization of two dienes that determines regio- and diastereoselectivity. Topographic steric maps derived from crystallographic data provided insights into the basis for the catalyst control through stereoselective oxidative cyclization and subsequent, stereospecific allyl-isomerization and C-C bond-forming reductive elimination.
Highly Diastereo- and Enantioselective Cu-Catalyzed Borylative Coupling of 1,3-Dienes and Aldimines
Jiang, Liyin,Cao, Peng,Wang, Min,Chen, Bin,Wang, Bing,Liao, Jian
supporting information, p. 13854 - 13858 (2016/10/26)
A Cu-catalyzed diastereo- and enantioselective borylative coupling reaction of 1,3-dienes with imines was realized. Branched homoallylic amines are readily prepared in a syn-selective manner with high regio-, diastereo- and enantioselectivity. Moreover, t
Microwave assisted synthesis of bridgehead alkenes
Cleary, Leah,Yoo, Hoseong,Shea, Kenneth J.
supporting information; experimental part, p. 1781 - 1783 (2011/06/16)
A new, concise method to synthesize triene precursors for the type 2 intramolecular Diels-Alder reaction has been developed. Microwave irradiation of the trienes provides a convenient method for the synthesis of bridgehead alkenes. Higher yields, shorter
