TY - JOUR
T1 - Efficient hydrogenation of organic carbonates, carbamates and formates indicates alternative routes to methanol based on CO 2 and CO
AU - Balaraman, Ekambaram
AU - Gunanathan, Chidambaram
AU - Zhang, Jing
AU - Shimon, Linda J.W.
AU - Milstein, David
N1 - Funding Information:
This research was supported by the European Research Council under the FP7 framework (ERC no. 246837), by the Israel Science Foundation, and by the MINERVA Foundation. D.M. is the Israel Matz Professorial Chair of Organic Chemistry.
PY - 2011/8
Y1 - 2011/8
N2 - Catalytic hydrogenation of organic carbonates, carbamates and formates is of significant interest both conceptually and practically, because these compounds can be produced from CO 2 and CO, and their mild hydrogenation can provide alternative, mild approaches to the indirect hydrogenation of CO 2 and CO to methanol, an important fuel and synthetic building block. Here, we report for the first time catalytic hydrogenation of organic carbonates to alcohols, and carbamates to alcohols and amines. Unprecedented homogeneously catalysed hydrogenation of organic formates to methanol has also been accomplished. The reactions are efficiently catalysed by dearomatized PNN Ru(II) pincer complexes derived from pyridine- and bipyridine-based tridentate ligands. These atom-economical reactions proceed under neutral, homogeneous conditions, at mild temperatures and under mild hydrogen pressures, and can operate in the absence of solvent with no generation of waste, representing the ultimate 'green' reactions. A possible mechanism involves metal-ligand cooperation by aromatization-dearomatization of the heteroaromatic pincer core.
AB - Catalytic hydrogenation of organic carbonates, carbamates and formates is of significant interest both conceptually and practically, because these compounds can be produced from CO 2 and CO, and their mild hydrogenation can provide alternative, mild approaches to the indirect hydrogenation of CO 2 and CO to methanol, an important fuel and synthetic building block. Here, we report for the first time catalytic hydrogenation of organic carbonates to alcohols, and carbamates to alcohols and amines. Unprecedented homogeneously catalysed hydrogenation of organic formates to methanol has also been accomplished. The reactions are efficiently catalysed by dearomatized PNN Ru(II) pincer complexes derived from pyridine- and bipyridine-based tridentate ligands. These atom-economical reactions proceed under neutral, homogeneous conditions, at mild temperatures and under mild hydrogen pressures, and can operate in the absence of solvent with no generation of waste, representing the ultimate 'green' reactions. A possible mechanism involves metal-ligand cooperation by aromatization-dearomatization of the heteroaromatic pincer core.
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U2 - 10.1038/nchem.1089
DO - 10.1038/nchem.1089
M3 - Article
C2 - 21778980
AN - SCOPUS:79960680595
VL - 3
SP - 609
EP - 614
JO - Nature Chemistry
JF - Nature Chemistry
SN - 1755-4330
IS - 8
ER -