Premium
A General One‐Pot Synthesis of 2 H ‐Indazoles Using an Organophosphorus–Silane System
Author(s) -
Schoene Jens,
Bel Abed Hassen,
Schmieder Peter,
Christmann Mathias,
Nazaré Marc
Publication year - 2018
Publication title -
chemistry – a european journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.687
H-Index - 242
eISSN - 1521-3765
pISSN - 0947-6539
DOI - 10.1002/chem.201800763
Subject(s) - regioselectivity , silanes , reagent , chemistry , indazole , silane , combinatorial chemistry , organic chemistry , oxide , catalysis
A simple and direct approach for the regioselective construction of the privileged 2 H ‐indazole scaffold is described. The developed one‐pot strategy involves phospholene‐mediated N−N bond formation to access 2 H ‐indazoles. The amount of organophosphorus reagent was minimized by recycling the phospholene oxide with organosilane reductants. Starting from functionalized 2‐nitrobenzaldehydes and primary amines, a mild reductive cyclization, involving the use of commercially available phospholene oxide and silanes, delivered a wide variety of substituted 2 H ‐indazoles in good to excellent yields.