Available spectroscopic labelling and reactivity data show that stable mu-nitrido diiron phthalocyanine activates H(2)O(2) to form a high-valent diiron oxo species This species is a very powerful oxidant which oxidizes methane in pure water at 25-60 C to methanol formaldehyde and formic acid The catalytic activity can significantly be increased in the presence of a diluted acid solution Thus a high turnover number of 209 was attained in 0 075 M H(2)SO(4) Oxidation of ethylene resulted in the formation of formic acid as a major product and formaldehyde with high turnover numbers Under optimal conditions 426 mol HCOOH and 37 mol CH(2)O per mole of catalyst were obtained in pure water The practical and green features of this novel approach (H(2)O(2) as the clean oxidant water as the clean reaction medium easily accessible solid catalyst) as well as the relevance to biological oxidation (binuclear structure of bio-inspired complex) are of great importance both from practical and fundamental points of view (C) 2010 Elsevier B V All rights reserved