Higher coordinate cyanide and isocyanide complexes. 13. Crystal structure of the homoleptic seven-coordinate complex heptakis(tert-butyl isocyanide)chromium(II) hexafluorophosphate, [Cr(CN-t-Bu)7](PF6)2

Eightfold Electrophilic Methylation of Octacyanotungstate [W(CN)8]4–/3–: Preparation of Homoleptic, Eight-Coordinate Methyl Isocyanide Complexes [W(CNMe)8]4+/5+

“…11,14 Interestingly, the seven-coordinate chromium complex [Cr(CN t Bu) 7 ][PF 6 ] 2 also exists. 15 In contrast, octacyanometalates [M(CN) 8 ] 4−/3− (M = Mo, W) have been frequently used as building blocks in coordination chemistry. 16 Most relevant are their applications in magnetochemistry: 17 for example, for the preparation of photomagnetic materials 18 and single-molecule magnets.…”

“…13 C NMR (176 MHz, CD 3 CN, 25 °C): δ 31.82 (CNMe), 115.30 (CNMe). 15 N HMQC (71 MHz, CD 3 CN, 25 °C): δ 140 (CNMe). 19 F NMR (377 MHz, CD 3 CN, 25 °C): δ −79.21 (OTf).…”

“…13 C signals for the isocyanide carbon were in the range of 115.3 ppm (major component) and 112.5 ppm (minor component), while only one signal for the methyl group could be observed (δ 31.8 ppm). The 15 N HMQC spectrum revealed one signal at 141 ppm (referenced vs NH 3 ) that could be assigned to the isocyanide nitrogen. Although the crystal structure proves that methyl triflate is able to methylate [W(CN) 8 ] 4− eight times, the usefulness of this method is limited to the significant amounts of side products, which cannot be separated from the product.…”

“…For the latter complex, the corresponding tungsten compound was only briefly mentioned in the literature . For molybdenum, the crystal structures of [Mo­(CNR) 7 ]­[PF 6 ] 2 are also known (R = cyclohexyl, phenyl). , Interestingly, the seven-coordinate chromium complex [Cr­(CN t Bu) 7 ]­[PF 6 ] 2 also exists …”

Eightfold Electrophilic Methylation of Octacyanotungstate [W(CN)8]4−/3−: Preparation of Homoleptic, Eight-coordinate Methylisocyanide Complexes [W(CNMe)8]4+/5+

“…8,11 Interestingly, also a seven-coordinate chromium complex [Cr(CN t Bu)7][PF6]2 exists. 12 In contrast, octacyanometalates [M(CN)8] 4−/3− (M= Mo, W) have been frequently used as building blocks in coordination chemistry. 13 Most relevant are their applications in magnetochemistry, 14 for example for the preparation of photomagnetic materials 15 and single-molecule magnets.…”