The
complex [Mo(CO)(PhC
![](/images/entities/tbd1.gif)
CPh)
2(
![](/images/gif<font color=)
chars/eta.gif" BORDER=0 >
5-C
5Me
5)][BF
4] rea
cts with 3 equiv of CNBu
t to yieldthe mixed alkyne-iso
cyanide
complex [Mo(CNBu
t)
3(PhC
![](/images/entities/tbd1.gif)
CPh)(
![](/images/gif<font color=)
chars/eta.gif" BORDER=0 >
5-C
5Me
5)][BF
4],
1. Rea
ctionof
1 with a fourth equivalent of CNBu
t generates [Mo{=C(NHBu
t)C(Ph)=C(Ph)CN}(CNBu
t)
2(
![](/images/gif<font color=)
chars/eta.gif" BORDER=0 >
5-C
5Me
5)][BF
4],
2,
containing an
![](/images/gif<font color=)
chars/eta.gif" BORDER=0 >
3-vinyl
carbene ligand formed from the
coupling of two ofthe
coordinated iso
cyanide ligands with the diphenyla
cetylene, with
con
comitant protonationof one of these iso
cyanide fragments and dealkylation of the other. Complex
2 may bedeprotonated to give [Mo{C(=NBu
t)C(Ph)=C(Ph)CN}(CNBu
t)
2(
![](/images/gif<font color=)
chars/eta.gif" BORDER=0 >
5-C
5Me
5)],
3. Protonation of
1 with HBF
4·Et
2O generates [Mo{=C(Ph)C(Ph)C=NHBu
t}(CNBu
t)
2(
![](/images/gif<font color=)
chars/eta.gif" BORDER=0 >
5-C
5Me
5)][BF
4]
2,
4, byindu
cing the
coupling of a protonated iso
cyanide ligand with diphenyla
cetylene, and
4 rea
ctswith CNBu
t to give
2. A similar rea
ction of
4 with P(OMe)
3 generates [Mo{=C(NHBu
t)C(Ph)=C(Ph)CN}(CNBu
t){P(OMe)
3}(
![](/images/gif<font color=)
chars/eta.gif" BORDER=0 >
5-C
5Me
5)][BF
4],
5, involving the same
coupling andelimination pattern. The diphenyla
cetylene and CNBu
t ligands of
1 may also be redu
ctively
coupled. Thus, treatment of
1 with sodium-mer
cury amalgam and subsequent protonationwith HBF
4·Et
2O gives the metalla
cy
clopentatriene-like [Mo{=C(NHBu
t)C(Ph)=C(Ph)C(NHBu
t)}(CNBu
t)(
![](/images/gif<font color=)
chars/eta.gif" BORDER=0 >
5-C
5Me
5)][BF
4],
6, or [Mo{=C(NHBu
t)C(Ph)C(Ph)CH-NHBu
t}(CNBu
t)(
![](/images/gif<font color=)
chars/eta.gif" BORDER=0 >
5-C
5Me
5)][BF
4],
7, depending upon the solvent. Complex
7 contains an
N-protonated
![](/images/gif<font color=)
chars/eta.gif" BORDER=0 >
4-monoazadiene ligand with a pendant
carbene fun
ctionality that is also
coordinated to themetal. The
crystal stru
ctures of
1,
2,
3,
6, and
7 have been determined.