1,2,3-Diheterocyclizations at the allenylidene ligand in the complex [(triphos)(CO)
2Re{C=C=CPh
2}]OTf (
1; triphos = MeC(CH
2PPh
2)
3, OTf = OSO
2CF
3) readily occur upon reacting
1 with N
,N-heterocyclessuch as 1
H-benzotriazole, 2-aminopyridine, and 2-aminothiazole. The reaction of
1 with 1
H-benzotriazoleleads to
[(triphos)(CO)2Re{C=C(H)C(Ph)}]N(C6H4)N=N}]OTf (
4). Deprotonation of
4 with sodiummethoxide in tetrahydrofuran at room temperature yields the alkynyl derivative
[(triphos)(CO)2Re{C
CC(Ph)2(NC6H4N=N)}] (
5) via ring opening of the triazaindenyl moiety in
4. Reaction of
1 with2-aminopyridine or 2-aminothiazole in CH
2Cl
2 leads to the heterobicyclic compounds
[(triphos)(CO)2Re{C=C(H)C(Ph)2N(H)C(CH)4N}]OTf (
6) and
[(triphos)(CO)2Re{C=C(H)C(Ph)2N(H)CS(CH)2N}]OTf(
8), respectively. Both complexes undergo regioselective deprotonation at the N-H heterocycle groupby treatment with sodium methoxide in THF, giving the neutral species
[(triphos)(CO)2Re{C=C(H)C(Ph)2NC(CH)4N}] (
7) and
[(triphos)(CO)2Re{C=C(H)C(Ph)2NCS(CH)2N}] (
9), respectively. The X-raystructures of the new organorhenium species
4 and
7-
9 have been determined, which have confirmedthat the addition of the NH bond of the N
,N-heterocycle occurs always across the C
![](/images/gifchars/beta2.gif)
-C
![](/images/gifchars/gamma.gif)
double bondof the allenylidene chain.