Selective deoxygenation of nitrate to nitrosyl using trivalent chromium and the Mashima reagent: reductive silylation† †Electronic supplementary information (ESI) available: NMR, MS (ESI, APCI), FT-IR, EPR, XPS, CV, DFT, and crystal structure data for H2LCr(NO3)2(NO). CCDC 1848665. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c8sc02979b

1,4-Bis(trimethylsilyl)-1,4-diaza-2,5-cyclohexadiene is an effective silyl transfer reagent towards the oxygen of nitrate coordinated to Cr( iii ) in a pincer complex. 1,4-Bis(trimethylsilyl)-1,4-diaza-2,5-cyclohexadiene is an effective silyl transfer reagent towards the oxygen of nitrate coordinated to Cr( iii ) in a pincer complex. Two nitrate oxygens are removed to give the 17 valence electron octahedral complex (H 2 L)Cr(NO 3 ) 2 (NO). This is shown by a variety of spectroscopic methods, together with DFT, to be a Cr( i ) complex with a linear CrNO unit. This work also identifies future applications of this reductive silylation process.