title: High-Temperature Continuous-Flow Zincations of Functionalized Arenes and Heteroarenes Using (Cy2N)2Zn·2LiCl.
abstract: The treatment of sensitive arenes and heteroarenes with the zinc bis-amide (Cy2N)2Zn·2LiCl (0.55 equiv), prepared in quantitative yield by the reaction of Cy2NLi with ZnCl2, leads under flow conditions to a fast zincation within 10 min at temperatures between 25 and 100 °C. The resulting organozinc reagents can be trapped with various organic halides (allylic bromides, aryl iodides) in high yields. Moreover, complementary metalation regioselectivities can be obtained for several substituted pyridines compared to commonly used LiCl-activated TMP-zinc (TMP = 2,2,6,6-tetramethylpiperidyl) and -magnesium bases.
authors.affiliation: Department of Chemistry, Ludwig-Maximilians-Universität , Butenandtstrasse 5-13, 81377 Munich, Germany.
authors.forename: Matthias R
authors.initials: MR
authors.lastname: Becker
authors.affiliation: Department of Chemistry, Ludwig-Maximilians-Universität , Butenandtstrasse 5-13, 81377 Munich, Germany.
authors.forename: Paul
authors.initials: P
authors.lastname: Knochel