%0 Journal Article
%A Issberner, Karin
%A Niecke, Edgar
%A Wittchow, Eric
%A Dötz, Karl Heinz
%A Nieger, Martin
%D 1997
%T The 1-Phosphaallyl Anion as a Versatile Building Block
in Reactions with Alkynes and Fischer-Type
Alkynyltungsten Carbene Complexes†
%U https://acs.figshare.com/articles/journal_contribution/The_1-Phosphaallyl_Anion_as_a_Versatile_Building_Block_in_Reactions_with_Alkynes_and_Fischer-Type_Alkynyltungsten_Carbene_Complexes_sup_sup_/3779100
%R 10.1021/om960984u.s001
%2 https://acs.figshare.com/ndownloader/files/5890068
%K vinylphosphino
%K Versatile Building Block
%K OCH
%K metal carbene
%K acyclic
%K protonation
%K Tol
%K CH
%K dihydrophosphole 8
%K diphenyl substitution pattern
%K alkynyl carbene
%K CO
%K Thermal decarbonylation
%K tungsten methoxy alkynyl carbene
%K reaction pathway
%X The anionic 1,3-cycloaddition reaction of the
(1,2,3-triphenyl-1-phosphaallyl)lithium species
Li(dme)3[PhP−CPhC(Ph)H]
(1) with diphenylacetylene followed by protonation of
the
anionic intermediate 2 gave diastereoselectively
1,2,3,4,5-pentaphenyl-2,3-dihydrophosphole
(3). The relative
cis,trans-stereochemistry of the C4,C5,P-unit has
been established by X-ray
structure analysis. Addition of 1 to the Fischer-type
tungsten amino alkynyl carbene complex
(CO)5WC[N(CH2)4]−C⋮CPh
(4) yielded, after protonation, the metal carbene
modified
dihydrophosphole 8, which, in contrast, exhibits a
trans,trans-diphenyl substitution pattern.
Thus, a different reaction pathway is suggested, containing an
acyclic intermediate, which
could be trapped by deuteration to give the
(vinylphosphino)vinylcarbene complex
(CO)5WC[N(CH2)4]−CDC(Ph)−P(Ph)−CPhC(Ph)H
(10). Thermal decarbonylation of 10 led to
the
chelate complex
(CO)4WC[N(CH2)4]−CDC(Ph)−P(Ph)−CPhC(Ph)H
(11). The reaction
of 1 with the tungsten methoxy alkynyl carbene complex
(CO)5WC−(OCH3)−C⋮C(p-Tol)
(5) and subsequent protonation afforded the acyclic
(vinylphosphino)vinyl carbene complex
(CO)5WC(OCH3)−CHC(p-Tol)−P(Ph)−CPhC(Ph)H
(9), which underwent rearrangement
to the allenyl(vinyl)phosphane complex
[(OCH3)CHCC(p-Tol)][PhCC(H)Ph](Ph)P[W(CO)5]Ph−CPhC(Ph)H (12).
%I ACS Publications