The preparation and characterization of iron(II)hydride
complexes containing the tripodal tetraphosphineligandtris[2-(dimethylphosphino)ethyl]phosphine,P(CH
2CH
2PMe
2)
3(PP
3),
1, are reported. Dissolution of thechlorohydride
complex FeHCl(PP
3),
2, in methanolaffords an equili
brium mixture of
2 and the methoxy hydrido
complexFeH(OMe)(PP
3),
3. Reaction of amethanol solution containing
2 and
3 with anionicor neutral ligands affordsthe corresponding hydrido
complexes: reaction with NaBr affo
rdsFeHBr(PP
3),
4; reaction with NaI affordsFeHI(PP
3),
5; reaction with NaN
3 affordsFeHN
3(PP
3),
6; reaction with COaffords [FeH(CO)(PP
3)]
+,
7; reaction withN
2 affords[FeH(N
2)(PP
3)]
+,
8; and reaction with PPh
3 affords[FeHPPh
3(PP
3)]
+,
9. In some cases, further reactionof the product iron hydride
complexes is observed. Reaction ofFeHN
3(PP
3),
6, withNaN
3 for an extendedperiod affordsFe(N
3)
2(PP
3),
10. On standing in solution,[FeH(N
2)(PP
3)]
+,
8, is converted to the dinitrogen-
bridged
complex[FeH(PP
3)N
NFeH(PP
3)]
2+,
11. The carbonyl hydride
complex
7 and thedinitrogen hydride
complex
8 can be deprotonated to give the neutraliron(0)
complexes Fe(CO)(PP
3),
12, and Fe(N
2)(PP
3),
13,respectively. The air-sensitive
complexes
4-
13 were characterized, by multinuclear NMR,IR, Raman, and massspectroscopy and by elemental analysis.