118474-94-5Relevant articles and documents
Molecular Engineering of β-Substituted Oxoporphyrinogens for Hydrogen-Bond Donor Catalysis
Chahal, Mandeep K.,Payne, Daniel T.,Matsushita, Yoshitaka,Labuta, Jan,Ariga, Katsuhiko,Hill, Jonathan P.
supporting information, p. 82 - 90 (2020/01/02)
A new class of bifunctional hydrogen-bond donor organocatalyst using oxoporphyrinogens having increased intramolecular hydrogen-bond donor distances is reported. Oxoporphyrinogens are highly non-planar rigid macrocycles containing a multiple hydrogen bond-forming binding site. In this work, we describe the first example of non-planar OxPs as hydrogen-bond donor catalysts prepared using a molecular engineering approach of the binding site for dual activation of substrates. The introduction of β-substituents is key to the catalytic activity and the catalysts are able to catalyze 1,4-conjugate additions and sulfa-Michael additions, as well as, Henry and aza-Henry reactions at low catalyst loadings (≤ 1 mol-%) under mild conditions. Preliminary mechanistic studies have been carried out and a possible reaction mechanism has been proposed based on the bi-functional activation of both substrates through hydrogen-bonding interactions.
β-selective C-H arylation of pyrroles leading to concise syntheses of lamellarins C and I
Ueda, Kirika,Amaike, Kazuma,Maceiczyk, Richard M.,Itami, Kenichiro,Yamaguchi, Junichiro
supporting information, p. 13226 - 13232 (2015/03/30)
The first general β-selective C-H arylation of pyrroles has been developed by using a rhodium catalyst. This C-H arylation reaction, which is retrosynthetically straightforward but results in unusual regioselectivity, could result in de novo syntheses of
Biomimetic total synthesis of (±)-8-oxoerymelanthine
Yoshida, Yuki,Mohri, Kunihiko,Isobe, Kimiaki,Itoh, Toshimasa,Yamamoto, Keiko
supporting information; experimental part, p. 6010 - 6015 (2009/12/08)
(Chemical Equation Presented) Erymelanthine 1 and 8-oxoerymelanthine 2 are unique erythrina alkaloids containing a pyridine ring. We synthesized (±)-8-oxoerymelanthine 2 in 2.0% overall yield using the following key reactions. The characteristic 6-5-6-6-m
