Table 2.

N₂RR Mediated by [Na(12-c-4)₂][P₃^XFe–N₂] Complexes^a

	cat	acid (equiv)	reductant (equiv)	NH3/Fe (equiv)	Yield NH3/H+ (%)
1b	5a	46d	50e	7.0 ± 1.0	46 ± 7
2	5b	46d	50e	2.5 ± 0.1	17 ± 1
3	5c	46d	50e	2.7 ± 0.2	17 ± 1
4c	-	54f	108g	12.8 ± 0.5	72 ± 3
5	5b	46f	50g	4.1 ± 0.9	27 ± 6
6	5c	46f	50g	3.6 ± 0.3	24 ± 2

^aCatalyst, acid, reductant, and Et₂O sealed in a Schlenk tube at −196 °C under an N₂ atmosphere, warmed to −78 °C, and stirred. For runs utilizing HBAr^F₄, reactions were stirred at −78 °C for 1 h, followed by stirring at room temperature for 45 min. For other runs, reactions were allowed to stir and warm to room temperature overnight. Yields are reported as an average of three runs.

^bFrom ref 3.

^cFrom ref 11. P₃^BFe⁺ was used as the precatalyst.

^dHBAr^F₄.

^eKC₈.

^f[H₂NPh₂][OTf].

^gCp*₂Co.