102236-53-3Relevant academic research and scientific papers
Efficient synthesis of an A-B-C-tricycle fragment for a structural model of tolyporphin
Hu, Bing C.,Zhou, Wei Y.,Liu, Zu L.,Cai, Chao J.,Xu, Shi C.
, p. 89 - 100 (2010)
An efficient stereocontrolled synthesis of an A-B-C-tricycle fragment 7 for a structural model of tolyporphin 3 is described. All the rings were prepared from readily available starting materials. One of the two key steps is a selective ring-opening reaction of the lactone cycle in bicyclolactam-lactone 17 to cyanopyrrolidone 18, which introduces the chirality into synthetic compounds. The other key step is the combination of A ring with B-C-bicycle via a two-time Eschenmoser sulfide contraction. A-B-C-tricycle fragment 7 allows a new approach toward tolypophin compounds and other uroporphinoids.
ELECTROPHILIC HETEROAROMATIC SUBSTITUTIONS. IX. BEHAVIOUR OF HALOGENOPYRROLES TOWARDS HYDROGEN HALIDES IN DIVERSE SOLVENTS
Giuliano, Francesco,Penna, Marina,Sleiter, Giancarlo
, p. 589 - 594 (2007/10/02)
The reactions of a series of α- and β-bromo and-chloropyrroles with hydrogen halides have been investigated both in aprotic and protic solvents in order to establish the true nature of the processes.Proto dehalogenation (reductive dehalogenation) has only been observed in position α in aprotic solvents able to scavenge the elemental halogen (or mixed halogen) formed, whereas halogen exchange reactions are the prevailing processes under protic conditions.Contrary to previous statements, halogen exchange can occur in both directions (Cl--->Br and Br--->Cl) and has been observed only in α position.
