Table 1.
Select Structural Data for Complexes 2–4, 6, and 7
| Fe–Xa | ∑C–X–Cb | ∑P–Fe–Pb | rc | |
|---|---|---|---|---|
| 2ad | 2.458 | 341.8 | 342.7 | 1.14h |
| 3ae | 2.417 | 332.8 | 345.8 | 1.12 |
| 4ad | 2.309 | 330.1 | 352.3 | 1.07 |
| 2b | 2.662 | 340.8 | 344.8 | 1.05h |
| 3b | 2.539 | 336.2 | 347.8 | 1.00 |
| 4b | 2.485 | 334.8 | 349.6 | 0.98 |
| 2c | 2.666 | 341.9 | 345.8 | 1.05h |
| 3c | 2.544 | 337.8 | 348.7 | 1.00 |
| 4c | 2.489 | 335.8 | 350.4 | 0.98 |
| 6f | 2.809 | 351.6 | 335.0 | 1.11 |
| 7g | 2.574 | 344.4 | 350.1 | 1.02 |
a
Units of angstroms (Å).
b
Units of degrees (°).
c
Ratio of the Fe–X bond length to the sum of the covalent radii (Fe: 1.32 Å; B: 0.84 Å; Al: 1.21 Å; Ga: 1.22 Å; from ref 32).
d
From ref 14. For 4a, values are an average of two independent molecules in the asymmetric unit.
e
Values obtained from a DFT geometry optimized structure.
f
From ref 24. In solution, the terminal dinitrogen species (AltraPhos)Fe–N2 is believed to be in equilibrium with its dinitrogen-bridged analogue, [(AltraPhos)Fe]2(μ-N2). The structural data presented here is for the latter complex.
g
From ref 25.
h
See footnote in ref 33.