The perfluorosulfanylvinyldiiron(I) complex
[Fe(CO)
3
}
2
µ-C(SMe)(CF
3
)C(CF
2
)}] 1 reacted with tertiary
phosphanes [L = PPh
3
or P(OMe)
3
] in
dichloromethane or chloroform at 60 °C to give high yields of
cycloferrathiapentadiene iron clusters. When the nucleophile was
PPh
3
, the salt 2 was obtained: formally, a
fluoride-ion transfer between two molecules of 1 generates the
anion
[Fe(CO)
3
}
2
µ-C(CF
3
)C(CF
3
)SMe}]
-
and addition of
PPh
3
at two separate sites produces the counter cation
[(Ph
3
P)(OC)
2
Feµ-CFC(PPh
3
)C(CF
3
)SMe}Fe(CO)
3
]
+
. In contrast,
with P(OMe)
3
the neutral derivative
[Fe(CO)
3
}
2
µ-CFC[PO(OMe)
2
]C(CF
3
)SMe}] 4 was formed. Thermally
induced CâF bond activation is a feature of these reactions. All
the reaction products have been characterized by elemental analysis and
IR,
1
H,
19
F,
31
P and
13
C NMR
spectroscopy. The solid-state structure of
[(Ph
3
P)(OC)
2
Feµ-CFC(PPh
3
)C(CF
3
)SMe}Fe(CO)
3
][Fe(CO)
3
}
2
µ-C(CF
3
)C(CF
3
)SMe
}] 2 has been established by single-crystal X-ray
analysis. The FeâFe bond in the cation
[2.716(2) Ã
] is appreciably longer than the
corresponding bond in the anion [2.570(2) Ã
].
Possible routes to the formation of 2 and 4 have been
investigated. The conversion of 1 into 4 has been
shown to involve an intermediate 3 which has been fully
characterized by
19
F,
31
P and
13
C NMR
spectroscopy.
全氟硫酰基
乙烯基二
铁(I)络合物 [Fe(CO) 3 } 2 µ-C(SMe)(CF 3 )C(CF 2 )}] 1 与叔膦 [L = PPh 3 或 P(OMe) 3 ]在
二氯甲烷或
氯仿中于 60 °C 下反应,得到高产率的环
铁硫戊二烯铁簇。当亲核体为 PPh 3 时,可得到盐 2:形式上,两个分子 1 之间的
氟离子转移产生阴离子[Fe(CO) 3 } 2 µ-C(CF 3 )C(CF 3 )SMe}] - 并在两个独立位点加入 PPh 3 产生阳离子[(Ph 3 P)(OC) 2 Feµ-CFC(PPh 3 )C(CF 3 )SMe}Fe(CO) 3 ] + 。与此相反,P(OMe) 3 的中性衍
生物 [Fe(CO) 3 } 2 µ-CFC[PO(OMe) 2 ]C(CF 3 )SMe}] 4 形成。4 形成。热诱导 CâF 键活化是这些反应的一个特点。所有反应产物都通过元素分析和红外光谱、1 H、19 F、31 P 和 13 C NMR 光谱进行了表征。通过单晶 X 射线分析,确定了 [(Ph 3 P)(OC) 2 Feµ-CFC(PPh 3 )C(CF 3 )SMe}Fe(CO) 3 ][Fe(CO) 3 } 2 µ-C(CF 3 )C(CF 3 )SMe }] 2 的固态结构。阳离子[2.716(2) à ]中的 FeâFe 键明显长于阴离子[2.570(2) à ]中的相应键。 研究了形成 2 和 4 的可能途径。1 转化为 4 的过程涉及到中间体 3,该中间体 3 已通过 19 F、31 P 和 13 C NMR 光谱完全表征。