Reactivity of (η3-allyl)dicarbonylnitrosyl iron complexes with dimethyl malonate and diisobutyl malonate

Abstract

In this paper, we describe the reactivity of our previously reported (η3-allyl)dicarbonylnitrosyl iron complexes (1–9). In this context, stoichiometric reactions of 1–9 with dimethyl malonate and di-iso-butyl malonate were carried out. The regioselectivity of the resulting products (10–25) was determined by gas chromatoraphic analysis of reaction mixtures. These products were purified by column chromatography and then structurally characterized by IR, 1H NMR, 13C NMR spectroscopies and mass spectrometry. Effect of different ligands L (L = CO, PPh3, SIMES (1,3-di-tert-butylimidazolium hexafluoro phosphate), BUSI(1,3-bis(2,4,6-trimethyl-phenyl)-4,5-dihydro-3H-imidazol-1-ium hexafluorophosphate)) and their influence on the substitution pattern has also been studied. The introduction of variable substituents exhibited diverse reactivities. Generally, it was observed that the reactivity decreased by increasing the size of substituentin (η3-allyl)dicarbonylnitrosyl iron complexes (1–9). Strong impact on the reactivity was observed due to substitution pattern of the allyl moiety. A considerable reduction in the conversion ratio from 81% to 68% was observed in repositioning the substituent from C-3 to C-2 position.

Keywords

• Iron
• Stoichiometric reactions
• Column chromatography
• Dimethyl malonate