Regio- and stereoselective C-C bond formation between alkynes: Synthesis of linear dienynes from alkynes

Article abstract of DOI:10.1021/om020493b

Reactions of the iridacyclopentadienes [Ir(-CH=CHCH=CH)(NCCH₃)(CO)(PPh₃)₂]⁺ (2a) and [Ir(-CH=C(CH₂)₄C=CH)(NCCH₃)(CO)(PPh₃ )₂]⁺ (2b) with RC≡CH (R = C₆H₅, p-C₆H₄CH₃) give linear conjugated dienynes (RC≡CCH=CHCH=CH₂ (3) and RC≡CCH=C(CH₂)₄C=CH₂ (5)) and benzene derivatives (RC₆H₅ (4) and RC₆H₃C₆H₈ (6, 6-aryl-1,2,3,4-tetrahydronaphthalene)). Linear conjugated dienynes 3 and 5 are exclusively obtained from the reactions of alkynyl iridacyclopentadienes [Ir(-CH=CHCH=CH)(C≡CR)(CO)(PPh₃)₂] (7) and [Ir(-CH=C(CH₂)₄C=CH)(C≡CR)(CO)(PPh₃) ₂] (8) (R = C₆H₅ (a), p-C₆H₄CH₃ (b), cyclohex-1-enyl (c)) with HOTf, respectively. The di- and trinuclear alkynyl iridacyclopentadienes p-C₆H₄(C≡CIr-CH=CHCH=CH)L₃)₂ (9a), p-C₆H₄(C≡CIrCH=C(CH₂)₄C=CH)L ₃)₂ (9b), and m,m-C₆H₃(C≡CIr(-CH=CHCH=CH)L₃)₃ (10) (L₃ = (CO)(PPh₃)₂) react with HOTf to produce the extended and conjugated dienynes p-C₆H₄(C≡CCH=CHCH=CH₂)₂ (11), p-C₆H₄(C≡CCH= C(CH₂)₄C=CH₂)₂ (12), and m,m-C₆H₃(C≡CCH=CHCH=CH₂)₃ (13), respectively, in high yields. Iridacyclohexadienes [Ir(-CH=CHCH=CHC(=CH-p-C₆H₄R′))(CO)(PPh₃) ₂]BF₄ (17, R′ = H (a), CH₃ (b)) are obtained from the reactions of 7 with HBF₄ through a C-C bond-forming reaction between the α-carbons of alkynyl and 1,3-butadiene-1,4-diyl ligands. Plausible reaction pathways are suggested for the C-C bond-forming reaction between RC=CH and 1,3-butadiene-1,4-diyl ligands of iridacyclopentadienes to produce linear dienynes.

Full text of DOI:10.1021/om020493b

Organometallics 2002, 21, 4785-4793
4785
Regio- a n d Ster eoselective C-C Bon d F or m a tion
betw een Alk yn es: Syn th esis of Lin ea r Dien yn es fr om
Alk yn es
Chong Shik Chin,* Mieock Kim, Hyungeui Lee, Soyoung Noh, and Kang Min Ok
Chemistry Department, Sogang University, Seoul 121-742, Korea
Received J une 24, 2002
Reactions of the iridacyclopentadienes [Ir(-CHdCHCHdCH)(NCCH3)(CO)(PPh3)2]+ (2a )
and [Ir(-CHdC(CH2)4CdCH)(NCCH3)(CO)(PPh3)2]+ (2b) with RCtCH (R ) C6H5, p-C6H4CH3)
give linear conjugated dienynes (RCtCCHdCHCHdCH2 (3) and RCtCCHdC(CH2)4CdCH2
(5)) and benzene derivatives (RC6H5 (4) and RC6H3C6H8 (6, 6-aryl-1,2,3,4-tetrahydronaph-
thalene)). Linear conjugated dienynes 3 and 5 are exclusively obtained from the reac-
tions of alkynyl iridacyclopentadienes [Ir(-CHdCHCHdCH)(CtCR)(CO)(PPh3)2] (7) and
[Ir(-CHdC(CH2)4CdCH)(CtCR)(CO)(PPh3)2] (8) (R ) C6H5 (a ), p-C6H4CH3 (b), cyclohex-
1-enyl (c)) with HOTf, respectively. The di- and trinuclear alkynyl iridacyclopentadienes
p-C6H4(CtCIr(-CHdCHCHdCH)L3)2 (9a ), p-C6H4(CtCIrCHdC(CH2)4CdCH)L3)2 (9b), and
m,m-C6H3(CtCIr(-CHdCHCHdCH)L3)3 (10) (L3 ) (CO)(PPh3)2) react with HOTf to produce
the extended and conjugated dienynes p-C6H4(CtCCHdCHCHdCH2)2 (11), p-C6H4(CtCCHd
C(CH2)4CdCH2)2 (12), and m,m-C6H3(CtCCHdCHCHdCH2)3 (13), respectively, in high
yields. Iridacyclohexadienes [Ir(-CHdCHCHdCHC(dCH-p-C6H4R′))(CO)(PPh3)2]BF4 (17, R′
) H (a ), CH3 (b)) are obtained from the reactions of 7 with HBF4 through a C-C bond-
forming reaction between the R-carbons of alkynyl and 1,3-butadiene-1,4-diyl ligands.
Plausible reaction pathways are suggested for the C-C bond-forming reaction between
RCtCH and 1,3-butadiene-1,4-diyl ligands of iridacyclopentadienes to produce linear
dienynes.
In tr od u ction
conjugated hexatrienes (RCHdC(CHdCH2)2, R-HE X)
and octatetraenes (H2CdCHCRdCHC(-CHdCH2)d
CHR, R2-OCT) produced from reactions of HCtCH
and RCtCH (R ) C6H5, p-C6H4CH3, cyclohex-1-enyl,
C(CH3)dCH2, C(CH3)3) in the presence of the cis-
dihydridoiridium(III) complex [Ir(H)2(NCCH3)2(PPh3)2]+,
which proceeds via the bis(alkenyl) complex 1 as de-
picted in eq 1.4
Transition-metal-mediated C-C bond formation be-
tween alkynes has been extensively investigated as an
efficient method for the synthesis of highly conjugated
organic compounds,1 which have attracted great interest
because of their utility in organic synthesis and unique
physical properties.2
During the investigation on iridium-mediated C-C
bond formation involving alkynes,3 we observed cross-
(1) (a) Burrows, A. D.; Green, M.; J effery, J . C.; Lynam, J . M.;
Mahon, M. F. Angew. Chem., Int. Ed. 1999, 38, 3043. (b) Kishimoto,
Y.; Eckerle, P.; Miyatake, T.; Kainosho, M.; Ono, A.; Ikariya, T.; Noyori,
R. J . Am. Chem. Soc. 1999, 121, 12035. (c) Haskel, A.; Wang, J . Q.;
Straub, T.; Neyroud, T. G.; Eisen, M. S. J . Am. Chem. Soc. 1999, 121,
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1991, 10, 525. (e) Gue´rin, F.; McConville, D. H.; Vittal, J . J .; Yap, G.
A. P. Organometallics 1998, 17, 1290. (f) Shirakawa, E.; Yoshida, H.;
Nakao, Y.; Hiyama, T. J . Am. Chem. Soc. 1999, 121, 4290. (g) Werner,
H.; Scha¨fer, M.; Wolf, J .; Peters, K.; von Schnering, H. G. Angew.
Chem., Int. Ed. Engl. 1995, 34, 191. (h) Esteruelas, M. A.; Garc´ıa-
Yebra, C.; Oliva´n, M.; On˜ate, E.; Tajada, M. A. Organometallics 2000,
19, 5098. (i) Klein, H.-F.; Mager, M. Organometallics 1992, 11, 3174.
(2) (a) Mawatari, Y.; Tabata, M.; Sone, T.; Ito, K.; Sadahiro, Y.
Macromolecules 2001, 34, 3776. (b) Bunz, U. H. F. Acc. Chem. Res.
2001, 34, 998. (c) Schulz, M.; Tretiak, S.; Chernyak, V.; Mukamel, S.
J . Am. Chem. Soc. 2000, 122, 452. (d) Zhao, Y.; Tykwinski, R. R. J .
Am. Chem. Soc. 1999, 121, 458. (e) Winkler, J . D. Chem. Rev. 1996,
96, 167.
This prompted us to look into the reactions of
RCtCH with other types of bis(alkenyl) complexes,
(3) (a) Chin, C. S.; Won, G.; Chong, D.; Kim, M.; Lee, H. Acc. Chem.
Res. 2002, 35, 218. (b) Chin, C. S.; Kim, M.; Lee, H. Organometallics
2002, 21, 1679. (c) Chin, C. S.; Cho, H.; Won, G.; Oh, M.; Ok, K. M.
Organometallics 1999, 18, 4810. (d) Chin, C. S.; Maeng, W.; Chong,
D.; Won, G.; Lee, B.; Park, Y. J .; Shin, J . M. Organometallics 1999,
18, 2210.
(4) Chin, C. S.; Lee, H.; Park, H.; Kim, M. Organometallics 2002,
21, 3889.
10.1021/om020493b CCC: $22.00 © 2002 American Chemical Society
Publication on Web 09/25/2002

4786 Organometallics, Vol. 21, No. 22, 2002
Chin et al.
iridacyclopentadienes prepared by reactions of
[Ir(NCCH3)(CO)(PPh3)2]+ with HCtCH and HCt
C(CH2)4CtCH.5 We now wish to report the formation
of linear dienynes that are regio- and stereoselectively
produced from the reactions of iridacyclopentadienes
with terminal alkynes and suggest plausible reaction
mechanisms.
Resu lts a n d Discu ssion
Iridacyclopentadienes 25 react with RCtCH to give
linear conjugated dienynes (3 and 5) and cyclization
products (4 and 6) at 50 °C (eqs 2 and 3).
F igu r e 1. ORTEP drawing of p-C6H4(CtCIr(-CHd
CHCHdCH)L3)2 (9a , L3 ) (CO)(PPh3)2). Selected bond
lengths (Å): Ir1-C1, 1.868(27); Ir1-C2, 2.131(42);
Ir1-C5, 1.976(52); Ir1-C6, 2.056(37). Selected bond angles
(deg): C2-Ir1-C1, 89.4(16); C5-Ir1-C1, 166.3(18);
C5-Ir1-C2, 77.1(18); C6-Ir1-C1, 98.7(15); C6-Ir1-C2,
171.8(16); C6-Ir1-C5, 94.8(18).
intermediates for cyclotrimerization of alkynes to give
benzene7 and fulvene8 derivatives.
To see further C-C coupling between alkynyl and
1,3-butadiene-1,4-diyl groups to produce highly ex-
tended and conjugated dienynes, di- and trinuclear
alkynyl iridacyclopentadienes 9 and 10 have been
prepared in the same manner used to prepare 7 and 8
(eqs 6 and 7).
Z dimers (RCtCCHdCHR) of RCtCH are exclusively
and catalytically obtained after the production of 3 and
4 in the presence of excess RCtCH. Complexes 2a and
2b are recovered in high yields from the reactions of
“Ir-A” with HCtCH and HCtC(CH2)4CtCH, respec-
tively.
Linear dienynes 3 and 5 are exclusively obtained from
the reactions of HOTf with alkynyl iridacyclopenta-
dienes 7 and 8, which are prepared in high yields from
the reactions of 2a and 2b, respectively6 (eqs 4 and 5).
These iridium(III) complexes 9 and 10 have been
unequivocally identified by detailed spectral data (1H,
1
13C, 31P NMR and H,13C-2D HETCOR) and FAB-mass
measurements and also by the crystal structure of 9a
(see Figure 1, Experimental Section, and Supporting
Information).
(7) (a) Hardesty, J . H.; Koerner, J . B.; Albright, T. A.; Lee, G.-Y. J .
Am. Chem. Soc. 1999, 121, 6055. (b) Takahashi, T.; Tsai, F.-Y.; Li, Y.;
Nakajima, K.; Kotora, M. J . Am. Chem. Soc. 1999, 121, 11093. (c)
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P. L.; Spicer, M. D. Organometallics 1999, 18, 197. (e) Lautens, M.;
Klute, W.; Tam, W. Chem. Rev. 1996, 96, 49.
To the best of our knowledge, no example has
been reported thus far for reactions of alkynes with
metallacyclopentadienes to give linear dienynes, while
metallacyclopentadienes are well-known to serve as
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J . Am. Chem. Soc. 1997, 119, 11086. (b) O’Connor, J . M.; Hiibner, K.;
Merwin, R.; Gantzel, P. K.; Fong, B. S. J . Am. Chem. Soc. 1997, 119,
3631. (c) Kim, H.-J .; Choi, N.-S.; Lee, S. W. J . Organomet. Chem. 2000,
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Compounds 8 were also prepared in the same manner as described
for 7 in this reference. See the Experimental Section for a detailed
characterization of 8.

Synthesis of Linear Dienynes from Alkynes
Organometallics, Vol. 21, No. 22, 2002 4787
Sch em e 1
Oligomeric organometallic compounds with conju-
gated bridges have been extensively studied with re-
spect to their chemical and physical properties.9 Those
R,ω-diyl groups (-CtC-p-C6H4CtC- and -CtC-m,m-
C6H3(CtC)2-) are frequently introduced as bridging
ligands to connect two and three metal units.9f,10 Reac-
tions of these metal complexes, on the other hand, have
been rarely reported, except that the C-C coupling
between a 1,3-butadiyne-1,4-diyl bridging ligand and
RHCdCd units of RHCdCdRhCtCCtCRhdCdCHR
gives the novel dinuclear compounds [L3RhC(dCHR)Ct
CCtCC(dCHR)RhL3] (R ) H, Ph, L3 ) (CO)(PiPr3)2).11
Highly extended and conjugated dienynes 11-13 are
obtained in high yields from reactions of 9 and 10 with
HOTf.
readily interacts with a neighboring hydrocarbyl ligand
to form a new C-C bond.13 The vinylidene intermediate
A then undergoes the C-C bond-forming reaction
between the vinylidene and the 1,3-butadiene-1,4-diyl
groups to give the iridacyclohexadienes B. The hydrogen
of the vinyl moiety of B (i.e., the deuterium of B-d )
seems close enough to the metal to interact with the
metal to undergo â-H elimination14 and thus give
complex C. Finally, the intermediate C undergoes a
reductive elimination to produce dienynes 3.
We recently observed that H+ exclusively attacks the
â-carbon of the alkynyl ligand rather than an R-carbon
of neighboring alkenyl ligands of the alkynyl bis-
(alkenyl) complexes 14 (eq 8).4 Iridacyclopentadienes 2
Dienynes 11-13 have been unequivocally identified
by detailed data (1H and 13C NMR, 1H decoupling, NOE
spectral data, GC/MS and FD/MS measurements; see
Experimental Section and Supporting Information).
Reactions of 2 with DCtCR and of 7 and 8 with DOTf
give the same products 3-d (for 2a and 7) and 5-d (for
2b and 8), respectively, containing one deuterium bound
to the terminal olefinic carbon. These results led us to
suggest the mechanism containing vinylidene interme-
diate A, as shown in Scheme 1.
Metal-vinylidenes (MdCdCHR) are frequently ob-
served and suggested in the reactions of metal alkynyls
with H+ and of metal compounds with terminal alkynes
(RCtCH).12,13 The R-carbon (MdCdCHR) of the vi-
nylidene group is known to be so electrophilic that it
do not react with HOTf, while other metallacyclopen-
tadienes (M ) Ti, Pd, Zr) are known to react with
electrophiles to give conjugated dienes.7b,15 Reactions of
7 with HOTf in the presence of CH3CN, however, give
RCtCH and 2a . It is therefore not likely that H+
attacks the R-carbon of the 1,3-butadiene-1,4-diyl group
or the iridium metal center of 7. The deuterium found
at the terminal olefinic carbon of 3-d may, therefore,
be understood by the deuterium transfer through the
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4788 Organometallics, Vol. 21, No. 22, 2002
Chin et al.
â-deuterium abstraction (B-d f C-d ) followed by the
reductive elimination of 3-d , as shown in Scheme 1.
While attempts to isolate the vinylidene com-
plexes A have been unsuccessful, the related carbene
complex [Ir(-CHdCHCHdCH)(dCOCH2CH2CH2)(CO)-
(PPh3)2]+ (16) could have been obtained from the reac-
tion of 3-butyn-1-ol with 2a presumably via the intramo-
lecular trapping of a vinylidene group with the pendant
hydroxyl group (eq 9), as shown in the previously
reported [Ir(CRdCRCRdCR)(dCOCH2CH2CH2)(CO)-
(PPh3)2]+ (R ) CO2CH3) by O’Connor et al.16
Formation of the iridacyclohexadiene intermediate B
from the C-C bond-forming reaction between R-carbons
of alkynyl and 1,3-butadiene-1,4-diyl ligands is sup-
ported by the presence of the iridacyclohexadienes 17,
isolated from reactions of 7 with the acid (HBF4) with
noncoordinating base (BF4-) (eq 10).
F igu r e 2. ORTEP drawing of [Ir(-CHdCHCHdCHC-
(dCH-p-C6H4CH3))(CO)(PPh3)2]+ (17b) with 50% prob-
ability thermal ellipsoids. Selected bond distances (Å):
Ir1-C1, 2.030(6); Ir1-C5, 2.078(6); Ir1-C14, 1.933(7);
Ir1-H12a, 1.945; C1-C2, 1.334(9); C2-C3, 1.422(10);
C3-C4, 1.351(9); C4-C5, 1.422(9); C5-C6, 1.357(8);
C6-C7, 1.437(9); C7-C12, 1.392(8); C12-H12a, 0.930;
C14-O, 1.136(7). Selected bond angles (deg): C14-Ir1-
C1, 89.3(3); C14-Ir1-C5, 179.6(2), C1-Ir1-C5, 90.5(3),
Ir1-C14-O1, 177.8(6); C5-Ir1-H12a, 83.42; C14-Ir1-
H12a, 96.33.
Sch em e 2
These 16-electron complexes 17 have been well
characterized by detailed spectral (1H, 13C, 31P NMR,
1H,13C-2D HETCOR, and 1H NOE) and elemental
analysis data and by X-ray crystallography of 17b (see
Figure 2, Experimental Section, and Supporting Infor-
mation).
The crystal structure of 17b shows an R-hydrogen of
the aryl group close enough to the metal to have an
agostic interaction in the absence of a base such as OTf-.
Only a few examples of agostic interaction by the aryl
hydrogen have been reported in phosphinoaryl com-
plexes, whereas agostic alkyl complexes are numerous.17
It is somewhat surprising not to observe dienynes 3
from reactions of 17 with OTf- or bases such as
CH3CN and CO. The cis aryl group of 17, however, flips
outward to be in a position trans to the iridium center
(eq 11).
1H NMR spectra of 17 show an upfield signal at δ
4.74-4.78 due to the ortho protons (the agostic ones) of
p-C6H4R′, while the ortho protons of p-C6H4R′ of 18 and
19 are seen in the phenyl region (δ 6.78-7.08).
These rearrangements (19 r 17 f 18) may be
understood by the resonance involving the iridaben-
zenes D and E (Scheme 2). The conversion D f E pro-
vides a vacant site for CO coordination to produce
the 18-electron dicarbonyl complexes 18. The related
transformation of iridacyclohexadienes (CPhdCPhCHd
13CH13CH2)IrL4 to (CH2CPhdCH13CHd13CPh)IrL4 (L4
) (PMe3)2(acac)) via iridabenzene intermediates was
previously reported by Hughes et al.18
(17) (a) Dani, P.; Toorneman, M. A. M.; van Klink, G. P. M.; van
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K. J . Am. Chem. Soc. 1998, 120, 12692. (d) Vigalok, A.; Uzan, O.;
Shimon, L. J . W.; Ben-David, Y.; Martin, J . M. L.; Milstein, D. J . Am.
Chem. Soc. 1998, 120, 12539. (e) Dani, P.; Karlen, T.; Gossage, R. A.;
Smeets, W. J . J .; Spek, A. L.; van Koten, G. J . Am. Chem. Soc. 1997,
119, 11317. (f) King, W. A.; Luo, X.-L.; Scott, B. L.; Kubas, G. J .; Zilm,
K. W. J . Am. Chem. Soc. 1996, 118, 6782. (g) Cooper, A. C.; Streib, W.
E.; Eisenstein, O.; Caulton, K. G. J . Am. Chem. Soc. 1997, 119, 9069.
(16) (a) O’Connor, J . M.; Hiibner, K.; Closson, A.; Gantzel, P.
Organometallics 2001, 20, 1482. (b) O’Connor, J . M.; Pu, L.; Rheingold,
A. L. J . Am. Chem. Soc. 1987, 109, 7578.

Synthesis of Linear Dienynes from Alkynes
Organometallics, Vol. 21, No. 22, 2002 4789
and 127.1 (P(C6H5)3). HETCOR (1H (500 MHz) f 13C (126
MHz)): δ 7.04 f 127.4; 6.98 f 124.0; 6.66 f 130.7; 6.51, 6.45
f 140.1; 1.70 f 33.2; 1.23 f 31.9; 0.79 f 24.6; 0.68 f
24.3. 31P{1H} NMR (81 MHz, CDCl3): δ 0.07 (s, IrPPh3). IR
(KBr, cm-1): 2112 (m, νCtC), 1992 (s, νCtO). Anal. Calcd for
IrP2OC53H45: C, 66.86; H, 4.76. Found: C, 66.89; H, 4.82.
It seems that the agostic hydrogen of 17 is so strongly
bound to the metal that the interaction is not broken
by a base such as OTf-, while both CH3CN and CO
coordinate to the metal to give the stable 18-electron
complexes 18 and 19 to inhibit the â-hydrogen elimina-
tion of vinyl hydrogen to give linear dienynes.
I r (-C H dC (C H 2 )4 C dC H )(C tC -p -C 6 H 4 C H 3 )(C O )-
(P P h 3)2 (8b). 1H NMR (500 MHz, CDCl3): δ 7.3-7.7 (m,
P(C6H5)3, 30H), 6.58-6.87 (AB quartet with ∆ν/J ) 17.5,
In conclusion, iridacyclopentadienes can be utilized
to prepare linear conjugated dienynes by C-C bond
formation between 1,3-butadiene-1,4-diyl ligands and
alkynes and reactions of this type can be further applied
to reactions with diynes and triynes to prepare highly
extended and conjugated organic compounds.
IrCtC-p-C6H4CH3, 4H), 6.52 and 6.50 (both br s, IrCHd
C(CH2)4CdCH, 2H), 2.26 (s, IrCtC-p-C6H4CH3, 3H) 1.71, 1.24,
0.80, and 0.69 (m, IrCHdC(CH2)4CdCH, 8H). 13C NMR (126
MHz, CDCl3): δ 174.3 (t, IrCO, J (C-P) ) 7.9 Hz), 153.1 (t,
Exp er im en ta l Section
Gen er a l In for m a tion . A standard vacuum system and
Schlenk type glassware were used in most of the experiments
in handling metal complexes, although most of the compounds
are stable enough to be handled in air.
J (C-P) ) 4.3 Hz) and 148.4 (s) (IrCHdC(CH2)4CdCH), 141.1
(t, J (C-P) ) 6.7 Hz, IrCHdC(CH2)4CdCH), 134.6 and 133.6
PhCtCD, HOTf, and DOTf were purchased from Aldrich,
(both s, Cipso of IrCtC-p-C6H4CH3), 130.6 and 128.1 (both s,
CH carbons of IrCtC-p-C6H4CH3), 112.6 (s, IrCtC-p-C6H4-
CH3), 88.1 (t, J (C-P) ) 14.7 Hz, IrCtC-p-C6H4CH3), 33.2, 31.9,
and 1,4-diethynylbenzene (p-C6H4(CtCH)2),19 1,3,5-triethy-
nylbenzene (m,m-C6H3(CtCH)3),10a [Ir(-CHdCHCHdCH)-
(NCCH3)(CO)(PPh3)2]OTf (2a ),5 [Ir(-CHdC(CH2)4CdCH)-
24.6, and 24.3 (s, IrCHdC(CH2)4CdCH), 21.2 (s, IrCtC-p-
C6H4CH3), 134.7, 131.8, 129.6, and 127.0 (P(C6H5)3). HETCOR
(1H (500 MHz) f 13C (126 MHz)): δ 6.86 f 128.1; 6.58 f 130.6;
6.52, 6.50 f 141.1; 2.26 f 21.2; 1.71 f 33.2; 1.24 f 31.9; 0.80
f 24.6; 0.69 f 24.3. 31P{1H} NMR (81 MHz, CDCl3): δ -0.07
(s, IrPPh3). IR (KBr, cm-1): 2112 (m, νCtC), 1991 (s, νCtO). Anal.
Calcd for IrP2OC54H47: C, 67.13; H, 4.90. Found: C, 67.15; H,
4.95.
(NCCH3)(CO)(PPh3)2]OTf (2b ),5 and Ir(-CHdCHCHdCH)-
(CtCR)(CO)(PPh3)2 (7, R ) C6H5 (a ), p-C6H4CH3 (b), cyclohex-
1-enyl (c))6 were prepared by the literature methods.
In str u m en ts. NMR spectra were recorded on a Varian 300
1
or 500 MHz spectrometer for H, a 75 or 126 MHz instrument
for 13C, and an 81 MHz spectrometer for 31P. Infrared spectra
were obtained on a Nicolet 205. Electronic absorption spectra
were measured with a Hewlett-Packard HP8453 diode array
spectrophotometer. Elemental analyses were carried out with
a Carlo Erba EA1108 instrument. Gas chromatography/mass
spectra were measured with a Hewlett-Packard HP 5890A VG-
trio 2000 at the Organic Chemistry Center, Sogang University.
FD mass measurements were carried out with a Micro Mass
Co. Autospec-Q at the SK research center. FAB mass mea-
surements were carried out with a J MS-HX110/110A tandem
mass spectrometer at the Korea Basic Science Institute.
Ir (-CHdC(CH2)4CdCH)(cycloh ex-1-en yl)(CO)(P P h 3)2
(8c). 1H NMR (500 MHz, CDCl3): δ 7.3-7.7 (m, P(C6H5)3,
30H), 6.46 and 6.43 (both br s, IrCHdC(CH2)4CdCH, 2H),
5.14 (s, IrCtCCdCH(CH2)3CH2), 1.94, 1.63, and 1.44 (m, IrCt
CCdCH(CH2)3CH2, 8H), 1.70, 1.17, 0.78, and 0.66 (m, IrCHd
C(CH2)4CdCH, 8H). 13C NMR (126 MHz, CDCl3): δ 174.5 (t,
Syn t h esis. P r ep a r a t ion of Ir (-CH dC(CH2)4CdCH )-
IrCO, J (C-P) ) 7.3 Hz), 153.0 (br s) and 148.2 (s) (IrCHd
C(CH2)4CdCH), 141.5 (t, J (C-P) ) 7.5 Hz, IrCHdC(CH2)4Cd
(CtCR)(CO)(P P h 3)2 (8, R ) P h (a ), p-C6H4CH3 (b), Cy-
cloh ex-1-en yl (c)). These compounds were prepared in a
manner similar to the literature method for 7.5 The yield
CH), 130.0 (s, IrCtCCdCH(CH2)3CH2), 125.8 (s, IrCtCCd
CH(CH2)3CH2), 114.7 (s, IrCtCCdCH(CH2)3CH2), 83.0 (t,
J (C-P) ) 12.5 Hz, IrCtCCdCH(CH2)3CH2), 33.2, 31.9, 24.6,
and 24.3 (s, IrCHdC(CH2)4CdCH), 30.3, 25.4, 22.8, and 22.1
of 8a was 0.086 g (94%) based on Ir(-CHdC(CH2)4CdCH)-
(CtCPh)(CO)(PPh3)2 (8a ).
Ir (-CHdC(CH2)4CdCH)(CtCP h )(CO)(P P h 3)2 (8a ). 1H
NMR (500 MHz, CDCl3): δ 7.3-7.7 (m, P(C6H5)3, 30H), 7.04,
6.98, and 6.66 (m, IrCtCC6H5, 5H), 6.51 and 6.45 (both br s,
(s, IrCtCCdCH(CH2)3CH2), 134.8, 131.9, 129.5, and 127.0
(P(C6H5)3). HETCOR (1H (500 MHz) f 13C (126 MHz)): δ 6.46,
6.43 f 141.5; 5.14 f 125.8; 1.94 f 25.4; 1.70 f 33.2; 1.63 f
30.3; 1.44 f 22.8, 22.1; 1.17 f 31.9; 0.78 f 24.6; 0.66 f 24.3.
31P{1H} NMR (81 MHz, CDCl3): δ -0.50 (s, IrPPh3). IR
(KBr, cm-1): 2094 (m, νCtC), 1997 (s, νCtO). Anal. Calcd for
IrP2OC53H49: C, 66.58; H, 5.17. Found: C, 66.50; H, 5.19.
P r ep a r a tion of th e Din u clea r Alk yn yl Ir id a cyclop en -
IrCHdC(CH2)4CdCH, 2H), 1.70, 1.23, 0.79, and 0.68 (m,
IrCHdC(CH2)4CdCH, 8H). 13C NMR (126 MHz, CDCl3): δ
174.3 (t, IrCO, J (C-P) ) 7.5 Hz), 153.1 (t, J (C-P) ) 4.4 Hz)
and 148.5 (s) (IrCHdC(CH2)4CdCH), 141.0 (t, J (C-P) ) 7.4
Hz, IrCHdC(CH2)4CdCH), 129.7 (s, Cipso of IrCtCC6H5), 130.7,
ta d ien es p-C6H4(CtCIr (-CHdCHCHdCH)L3)2 (9a ) a n d
p-C6H4(CtCIr (-CHdC(CH2)4CdCH)L3)2 (9b) (L3 ) (CO)-
127.4, and 124.0 (s, CH carbons of IrCtCC6H5), 112.6 (s,
IrCtCPh), 90.1 (t, J (C-P) ) 14.6 Hz, IrCtCPh), 33.2, 31.9,
(P P h 3)2). Compounds 9a and 9b were prepared in the same
manner as described below for 9a . The reaction mixture of 2a
(0.20 g, 0.2 mmol) and p-C6H4(CtCH)2 (0.013 g, 0.1 mmol) in
CHCl3 (15 mL) was stirred in the presence of NEt3 (0.04 mL,
0.3 mmol) at 25 °C for 12 h under nitrogen before the
precipitation of beige microcrystals of 9a , which were collected
by filtration, washed with MeOH (3 × 10 mL), and dried under
24.6, and 24.3 (s, IrCHdC(CH2)4CdCH), 134.7, 131.7, 129.6,
(18) (a) Hughes, R. P.; Trujillo, H. A.; Egan, J . W., J r.,; Rheingold,
A. L. J . Am. Chem. Soc. 2000, 122, 2261. (b) Hughes, R. P.; Trujillo,
H. A.; Rheingold, A. L. J . Am. Chem. Soc. 1993, 115, 1583.
(19) J ung, J . K.; Kim, D. K.; Cho, D. H.; Yoon, B. I.; Kim, K. S.
Polymer (Korea) 1993, 17, 67.

4790 Organometallics, Vol. 21, No. 22, 2002
Chin et al.
vacuum. The yield was 0.16 g (92%) based on p-C6H4(Ct
CIr(-CHdCHCHdCH)L3)2 (9a , L ) (CO)(PPh3)2).
P r ep a r a t ion
of
[Ir (-CH dCH CHdCH )(dCOCH 2-
CH2CH2)(CO)(P P h 3)2]OTf (16). A CHCl3 (10 mL) solution
of 2a (0.10 g, 0.1 mmol) and HCtCCH2CH2OH (0.01 mL, 0.14
mmol) was stirred at 50 °C for 1 h before n-pentane (20 mL)
was added to precipitate beige microcrystals of 16, which were
collected by filtration, washed with n-pentane (3 × 10 mL),
and dried under vacuum. The yield was 0.10 g (97%) based on
p-C6H4(CtCIr (-CHdCHCHdCH)L3)2 (9a , L ) (CO)-
(P P h 3)2). 1H NMR (500 MHz, CD2Cl2): δ 7.2-8.0 (m, P(C6H5)3,
60H), 6.98 and 6.85 (both m, IrCHdCHCHdCH, 4H), 6.46 (s,
IrCtCC6H4, 4H), 6.18 and 5.71 (both m, IrCHdCHCHdCH,
4H). 13C NMR (126 MHz, CD2Cl2): δ 174.2 (t, J (C-P) ) 7.4
Hz, IrCO), 149.8 (t, J (C-P) ) 7.4 Hz) and 147.4 (t, J (C-P) )
[Ir(-CHdCHCHdCH)(dCOCH2CH2CH2)(CO)(PPh3)2]OTf (16).
1H NMR (500 MHz, CDCl3): δ 7.3-7.5 (m, P(C6H5)3, 30H), 7.53
12.6 Hz) (IrCHdCHCHdCH), 144.0 and 140.1 (both s, IrCHd
and 7.51 (both m, IrCHdCHCHdCH, 2H), 5.89 and 5.85 (both
m, IrCHdCHCHdCH, 2H), 4.56 (t, J (H-H) ) 8.0 Hz, Ird
COCH2CH2CH2, 2H), 2.45 (t, J (H-H) ) 8.0 Hz, IrdCOCH2-
CHCHdCH), 129.9 (s, CH carbons of IrCtCC6H4), 127.4 (s,
Cipso of IrCtCC6H4), 113.9 (s, IrCtCC6H4), 87.6 (t, J (C-P) )
10.2 Hz, IrCtCC6H4), 134.8, 131.7, 129.8, and 127.2 (P(C6H5)3).
HETCOR (1H (500 MHz) f 13C (126 MHz)): δ 6.98 f 147.4;
6.85 f 149.8; 6.46 f 129.9; 6.18 f 144.0; 5.71 f 140.1. 31P-
{1H} NMR (81 MHz, CDCl3): δ -1.91 (s, IrPPh3). IR (KBr,
cm-1): 2107 (m, νCtC), 1997 (s, νCtO). MS (FAB): m/z 1718
CH2CH2, 2H), 1.10 (q, J (H-H) ) 8.0 Hz, IrdCOCH2CH2CH2,
2H). 13C NMR (126 MHz, CDCl3): δ 287.3 (t, J (C-P) ) 6.5
Hz, IrdCOCH2CH2CH2), 172.6 (t, J (C-P) ) 7.4 Hz, IrCO),
153.2 (t, J (C-P) ) 9.8 Hz) and 136.0 (t, J (C-P) ) 9.8 Hz)
[M+]. Anal. Calcd for Ir2P4O2C92H72
Found: C, 63.75; H, 4.10.
: C, 64.32; H, 4.22.
(IrCHdCHCHdCH), 148.7 and 148.1 (s, IrCHdCHCHdCH),
89.7 (s, IrdCOCH2CH2CH2), 55.8 (s, IrdCOCH2CH2CH2), 19.6
p-C6H4(CtCIr (-CHdC(CH2)4CdCH)L3)2 (9b, L3 ) (CO)-
(P P h 3)2). 1H NMR (500 MHz, CDCl3): δ 7.3-7.8 (P(C6H5)3,
(s, IrdCOCH2CH2CH2), 134.3, 131.6, 128.2, and 128.0 (P(C6H5)3).
HETCOR (1H (500 MHz) f 13C (126 MHz)): δ 7.53 f 153.2;
7.51 f 136.0; 5.89 f 148.1; 5.85 f 148.7; 4.56 f 89.7; 2.45 f
55.8; 1.10 f 19.6. 31P{1H} NMR (81 MHz, CDCl3): δ -1.15
(s, IrPPh3). IR (KBr, cm-1): 2032 (s, νCtO), 1265, 1151, and
1031 (s, due to uncoordinated OTf-). Anal. Calcd for IrP2O5-
SF3C46H40: C, 54.38; H, 3.97. Found: C, 54.40; H, 3.99.
60H), 6.49 and 6.48 (both br s, IrCHdC(CH2)4CdCH, 4H), 6.39
(s, IrCtCC6H4, 4H), 1.72, 1.22, 0.80, and 0.69 (IrCHd
C(CH2)4CdCH, 16H). 13C NMR (126 MHz, CDCl3): δ 174.3 (t,
IrCO, J (C-P) ) 7.0 Hz), 153.0 (br t, J (C-P) ) 3.8 Hz) and
148.3 (s) (IrCHdC(CH2)4CdCH), 141.5 (br t, J (C-P) ) 7.1 Hz,
P r ep a r a tion of [Ir (CHdCHCHdCHC(dCH-p-C6H4R′))-
(CO)(P P h 3)2]BF 4 (17, R′ ) H (a ), CH3 (b)). These compounds
were prepared in the same manner as described below for 17a .
A reaction mixture of 7a (0.10 g, 0.1 mmol) and HBF4 (0.016
mL, 54 wt % in Et2O) in CHCl3 (10 mL) was stirred for 1 h at
25 °C before Et2O (30 mL) was added to precipitate reddish
microcrystals, which were collected by filtration, washed with
n-pentane (3 × 10 mL), and dried under vacuum. The yield
IrCHdC(CH2)4CdCH), 129.8 (s, CH carbons of IrCtCC6H4),
127.6 (s, Cipso of IrCtCC6H4) 113.4 (s, IrCtCC6H4), 88.6 (t,
J (C-P) ) 15.2 Hz, IrCtCC6H4), 33.2, 31.9, 24.6, and 24.3 (s,
IrCHdC(CH2)4CdCH), 134.7, 131.8, 129.5, and 127.0 (P(C6H5)3).
HETCOR (1H (500 MHz) f 13C (126 MHz)): δ 6.49, 6.48 f
141.5; 6.39 f 129.8; 1.72 f 33.2; 1.22 f 31.9; 0.80 f 24.6;
0.69 f 24.3. 31P{1H} NMR (81 MHz, CDCl3): δ -0.21 (s,
IrPPh3). IR (KBr, cm-1): 2106 (m, νCtC), 1995 (s, νCtO). MS
was 0.102 g (93%) based on [Ir(CHdCHCHdCHC(dCHC6H5))-
(CO)(PPh3)2]BF4 (17a ).
(FAB): m/z 1626 [M+]. Anal. Calcd for Ir2P4O2C100H84
: C,
65.77; H, 4.64. Found: C, 65.79; H, 4.68.
P r ep a r a tion of th e Tr in u clea r Alk yn yl Ir id a cyclop en -
ta d ien e m ,m -C6H3(-CtCIr (-CHdCHCHdCH)L3)3 (10, L3
) (CO)(P P h 3)2). This compound was prepared in the same
manner as described above for 9a by using m,m-C6H3(-Ct
CH)3. The yield was 0.11 g (95%) based on m,m-C6H3(-Ct
CIr(CHdCHCHdCH)L3)3 (10, L3 ) (CO)(PPh3)2).
m ,m -C6H3(CtCIr (-CHdCHCHdCH)L3)3 (10, L3 ) (CO)-
(P P h 3)2). 1H NMR (500 MHz, CDCl3): δ 7.2-8.0 (m, P(C6H5)3,
[Ir (CHdCHCHdCHC(dCHC6H5))(CO)(P P h 3)2]BF4 (17a).
1H NMR (500 MHz, CDCl3): δ 7.1-7.5 (m, P(C6H5)3 and H9,
32H), 6.92 (t, J (H-H) ) 7.5 Hz, H10), 6.82 (t, J (H-P) ) 4 Hz,
H6), 6.64 (m, H1), 5.88 (br d, J (H-H) ) 10.0 Hz, H4), 5.50 (br
90H), 7.06 and 6.74 (both m, IrCHdCHCHdCH, 6H), 6.52 (s,
CH carbons of IrCtCC6H3, 3H), 6.29 and 5.67 (both m, IrCHd
t, J (H-H) ) 6.9 Hz, H2), 5.20 (m, H3), 4.74 (br m, H8, 2H). 13
C
NMR (126 MHz, CDCl3): δ 176.6 (t, J (C-P) ) 7.9 Hz, IrCO),
165.0 (t, J (C-P) ) 11.9 Hz, C5), 149.0 and 127.2 (s, C7 and
C9), 143.8 (t, J (C-P) ) 7.3 Hz, C6), 135.4 (s, C4), 127.9 (t,
J (C-P) ) 9.8 Hz, C1), 126.3 (br s, C3), 122.0 (t, J (C-P) ) 4.9
Hz, C2), 119.8 (br s, C8), 134.6, 131.8, 128.5, and 127.3
(P(C6H5)3). 31P{1H} NMR (81 MHz, CDCl3): δ 2.41 (s, IrPPh3).
IR (KBr, cm-1): 2052 (s, νCtO), 1064 (s, due to noncoordinated
CHCHdCH, 6H). 13C NMR (126 MHz, CDCl3): δ 174.1 (t,
J (C-P) ) 7.3 Hz, IrCO), 150.6 (t, J (C-P) ) 6.2 Hz) and 147.6
(t, J (C-P) ) 12.2 Hz) (IrCHdCHCHdCH), 144.0 and 139.5
(both s, IrCHdCHCHdCH), 130.1 (s, CH carbons of IrCt
CC6H3) 128.0 (s, Cipso of IrCtCC6H3), 114.2 (s, IrCtCC6H3),
84.9 (t, J (C-P) ) 14.6 Hz, IrCtCC6H3), 134.8, 131.9, 129.8,
and 127.2 (P(C6H5)3). HETCOR (1H (500 MHz) f 13C (126
MHz)): δ 7.06 f 147.6; 6.74 f 150.6; 6.52 f 130.1; 6.29 f
144.0; 5.67 f 84.9. 31P{1H} NMR (81 MHz, CDCl3): δ -2.75
(s, IrPPh3). IR (KBr, cm-1): 2103 (m, νCtC), 2000 (s, νCtO). MS
(FAB): m/z 2538 [M+]. Anal. Calcd for Ir3P6O3C135H105: C,
63.89; H, 4.17. Found: C, 63.36; H, 3.90.
BF4-). Anal. Calcd for IrP2OBF4C49H40
Found: C, 59.36; H, 3.94.
: C, 59.70; H, 4.09.
[Ir (CH dCH CH dCH C(dCH -p -C6H 4CH 3))(CO)(P P h 3)2]-
BF 4 (17b). 1H NMR (500 MHz, CDCl3): δ 7.35-7.45 (m,
P(C6H5)3, 30H), 7.28 (br d, J (H-H) ) 6.5 Hz, H9, 2H), 6.78 (br
t, J (H-P) ) 3.8 Hz, H6), 6.65 (m, H1), 5.79 (br d, J (H-H) )

Synthesis of Linear Dienynes from Alkynes
Organometallics, Vol. 21, No. 22, 2002 4791
10.0 Hz, H4), 5.55 (br t, J (H-H) ) 6.5 Hz, H2), 5.15 (m, H3),
4.78 (br m, H8, 2H), 2.25 (s, p-C6H4CH3, 3H). 13C NMR (126
MHz, CDCl3): δ 176.5 (t, J (C-P) ) 8.4 Hz, IrCO), 163.7 (t,
J (C-P) ) 12.2 Hz, C5), 147.2 and 137.7 (s, C7 and C10), 143.0
(t, J (C-P) ) 7.6 Hz, C6), 135.6 (s, C9) 134.9 (s, C4), 127.8 (t,
J (C-P) ) 9.4 Hz, C1), 125.7 (br s, C3), 122.1 (br s, C2), 118.9
(br s, C8), 20.6 (s, p-C6H4CH3), 134.6, 131.7, 128.4, and 127.3
(P(C6H5)3). HETCOR (1H NMR (500 MHz) f 13C NMR (126
MHz)): δ 7.28 f 135.6; 6.78 f 143.0; 6.65 f 127.7; 5.79 f
134.9; 5.55 f 122.1; 5.15 f 125.7; 4.78 f 118.9; 2.25 f 20.6.
31P{1H} NMR (81 MHz, CDCl3): δ 1.97 (s, IrPPh3). IR (KBr,
cm-1): 2050 (s, νCtO), 1057 (s, due to noncoordinated BF4-).
Anal. Calcd for IrP2OBF4C50H42: C, 60.06; H, 4.23. Found: C,
59.62; H, 4.04.
turned light brown. Excess Me3NO and NMe3 were removed
by extraction with H2O (2 × 10 mL). Addition of n-pentane
(20 mL) resulted in precipitation of beige microcrystals that
were collected by filtration, washed with n-pentane (3 × 10
mL), and dried under vacuum. The yield was 0.09 g (85%)
based on [Ir(CHdCHCHdCHC(dCHC6H5)(NCCH3)2(PPh3)2]-
BF4 (19a ).
[Ir (CH dCH CH dCH C(dCH C6H 5)(NCCH 3)2(P P h 3)2]-
1
BF 4 (19a ). H NMR (500 MHz, CDCl3): δ 8.22 (br d, J (H-H)
) 9.0 Hz, H1), 7.3-7.5 (m, P(C6H5)3, 30H), 7.22 (t, J (H-H) )
7.8 Hz, H9, 2H), 7.05 (t, J (H-H) ) 7.5 Hz, H10), 6.85 (d,
J (H-H) ) 7.5 Hz, H8, 2H), 6.29 (ddt, J (H-H) ) 9.0 Hz, J (H-
H) ) 6.5 Hz, J (H-P) ) 2.0 Hz, H2), 5.98 (d, J (H-H) ) 10.5
Hz, H4), 5.66 (s, H6), 5.38 (dd, J (H-H) ) 10.5 Hz, J (H-H) )
6.5 Hz, H3), 1.72 (br s, CH3CN, 6H). 13C NMR (126 MHz,
CDCl3): δ 133.7 (t, J (C-P) ) 7.6 Hz, C6), 131.0 (s, C3), 130.0
(t, J (C-P) ) 10.4 Hz, C1), 128.0 (br s, C2), 126.7 (br s, C4),
123.3 (t, J (C-P) ) 10.4 Hz, C5), 120.5 and 120.0 (s, CH3CN),
2.8 and 2.5 (s, CH3CN), 134.9, 131.3, 130.2, and 127.7
(P(C6H5)3). 31P{1H} NMR (81 MHz, CDCl3): δ -7.40 (s, IrPPh3).
1H NOE: irradiation of the signal at 6.01 ppm (H4) shows a
negative NOE effect on the signal at 5.68 ppm (H6). Anal. Calcd
for IrP2N2BF4C52H46: C, 60.06; H, 4.46; N, 2.69. Found: C,
59.95; H, 4.38; N, 2.54.
P r ep a r a tion of [Ir (CHdCHCHdCHC(dCH-p-C6H4R′))-
(CO)2(P P h 3)2]BF 4 (18, R′ ) H (a ), CH3 (b)). These com-
pounds were prepared in the same manner as described below
for 18a . A 0.1 g (0.1 mmol) amount of 17a in CHCl3 (10 mL)
was stirred under CO (1 atm) at 25 °C for 12 h before
n-pentane (30 mL) was added to precipitate beige microcrys-
tals, which were collected by filtration, washed with n-pentane
(3 × 10 mL), and dried under vacuum. The yield was 0.10 g
(97%)based on [Ir(CHdCHCHdCHC(dCHC6H5))(CO)2(PPh3)2]-
BF4 (18a ).
[Ir (CHdCHCHdCHC(dCH-p-C6H4CH3)(NCCH3)2(P P h 3)2]-
BF 4 (19b). H NMR (500 MHz, CDCl3): δ 8.18 (br d, J (H-H)
[Ir (CHdCHCHdCHC(dCHC6H5))(CO)2(P P h 3)2]BF4 (18a).
1H NMR (500 MHz, CDCl3): δ 7.4-7.6 (m, P(C6H5)3 and H1,
31H), 7.23 (t, J (H-H) ) 7.5 Hz, H9, 2H), 7.20 (t, J (H-H) )
7.5 Hz, H10), 6.90 (d, J (H-H) ) 7.5 Hz, H8, 2H), 6.40 (ddt,
J (H-H) ) 10 Hz, J (H-H) ) 6.5 Hz, J (H-P) ) 2.3 Hz, H2),
6.24 (br s, H6), 6.22 (d, J (H-H) ) 11 Hz, H4), 5.42 (dd,
J (H-H) ) 11 Hz, J (H-H) ) 6.5 Hz, H3). 13C NMR (126 MHz,
CDCl3): δ 168.0 (t, J (C-P) ) 6.9 Hz, IrCO), 164.4 (t, J (C-P)
) 6.3 Hz, IrCO), 143.4 (t, J (C-P) ) 7.5 Hz, C6), 140.4 (s, C7),
131.6 (br s, C3), 130.9 (t, J (C-P) ) 4.4 Hz, C2), 129.0 (s, C8),
128.1 (br s, C4), 127.8 (s, C9), 126.5 (s, C10), 124.0 (t, J (C-P) )
10.7 Hz, C5), 121.8 (t, J (C-P) ) 11.3 Hz, C1), 134.5, 132.0,
128.6, and 127.5 (P(C6H5)3). HETCOR (1H NMR (500 MHz) f
13C NMR (126 MHz)): δ ca. 7.5 f 121.8; 6.39 f 130.9; 6.24 f
143.4; 6.22 f 128.1; 5.42 f 131.6. 31P{1H} NMR (81 MHz,
CDCl3): δ -15.13 (s, IrPPh3). IR (KBr, cm-1): 2114, 2075 (s,
1
) 9.0 Hz, H1), 7.3-7.6 (m, P(C6H5)3, 30H), 6.77-7.06 (AB
quartet with ∆ν/J ) 34.24, p-C6H4CH3, 4H), 6.29 (ddt,
J (H-H) ) 9.0 Hz, J (H-H) ) 6.5 Hz, J (H-P) ) 2.0 Hz, H2),
6.02 (d, J (H-H) ) 10.5 Hz, H4), 5.60 (br s, H6), 5.36 (dd,
J (H-H) ) 10.5 Hz, J (H-H) ) 6.5 Hz, H3), 2.33 (s, p-C6H4CH3,
3H), 1.77 and 1.72 (br s, CH3CN, 6H). 13C NMR (126 MHz,
CDCl3): δ 133.7 (t, J (C-P) ) 7.0 Hz, C6), 130.8 (s, C3), 129.7
(t, J (C-P) ) 10.1 Hz, C1), 127.9 (t, J (C-P) ) 5.5 Hz, C2), 127.0
(br s, C4), 122.0 (t, J (C-P) ) 10.4 Hz, C5), 120.4 and 119.7 (s,
CH3CN), 21.0 (s, p-C6H4CH3), 3.1 and 2.7 (s, CH3CN), 134.9,
130.9, 130.2, and 127.6 (P(C6H5)3). HETCOR (1H NMR (500
MHz) f 13C NMR (126 MHz)): δ 8.18 f 129.7; 6.29 f 127.9;
6.02 f 127.0; 5.60 f 133.7; 5.36 f 130.8; 2.33 f 21.0; 1.77
and 1.72 f 3.1 and 2.7. 31P{1H} NMR (81 MHz, CDCl3): δ
-7.49 (s, IrPPh3). Anal. Calcd for IrP2N2BF4C53H48: C, 60.40;
H, 4.59; N, 2.66. Found: C, 60.48; H, 4.43; N, 2.59.
ν
CtO), 1060 (s, due to noncoordinated BF4-). Anal. Calcd for
IrP2O2BF4C50H40: C, 59.23; H, 3.98. Found: C, 59.15; H, 3.91.
Rea ction s. Rea ction s of 7 a n d 8 w ith H(D)OTf: F or -
m a tion of Dien yn es RCtCCHdCHCHdCH2 (3) a n d RCt
[Ir (CHdCHCHdCHC(dCH-p-C6H4CH3))(CO)2(P P h 3)2]-
BF 4 (18b). 1H NMR (500 MHz, CDCl3): δ 7.3-7.5 (m, P(C6H5)3
and H1, 31H), 6.8-7.1 (AB quartet with ∆ν/J ) 21.31, p-C6H4-
CH3, 4H), 6.40 (ddt, J (H-H) ) 10 Hz, J (H-H) ) 6.5 Hz,
J (H-P) ) 2.5 Hz, H2), 6.22 (br s, H6), 6.21 (d, J (H-H) ) 10.5
Hz, H4), 5.37 (dd, J (H-H) ) 10.5 Hz, J (H-H) ) 6.5 Hz, H3),
2.34 (s, p-C6H4CH3, 3H). 13C NMR (126 MHz, CDCl3): δ 168.1
(t, J (C-P) ) 7.4 Hz, IrCO), 164.5 (t, J (C-P) ) 5.5 Hz, IrCO),
143.5 (t, J (C-P) ) 7.5 Hz, C6), 137.5 and 136.4 (s, C7 and C10),
131.3 (br s, C3), 131.0 (t, J (C-P) ) 5.0 Hz, C2), 128.9 and 128.5
(s, C8 and C9), 128.2 (br s, C4), 124.5 (t, J (C-P) ) 10.7 Hz,
C5), 121.3 (t, J (C-P) ) 11.3 Hz, C1), 21.1 (s, p-C6H4CH3), 134.5,
132.0, 128.6, and 127.4 (P(C6H5)3). HETCOR (1H NMR (500
MHz) f 13C NMR (126 MHz)): δ ca. 7.4 f 121.3; 6.37 f
131.0; 6.22 f 143.5; 6.21 f 128.2; 5.37 f 131.3; 2.34 f 21.1.
31P{1H} NMR (81 MHz, CDCl3): δ -15.16 (s, IrPPh3). IR (KBr,
cm-1): 2116, 2080 (s, νCtO), 1057 (s, due to noncoordinated
BF4-). Anal. Calcd for IrP2O2BF4C54H42: C, 60.96; H, 3.98.
Found: C, 60.73; H, 3.87.
CCHdC(CH2)4CdCH2 (5, R ) P h (a ), p-C6H4CH3 (b),
Cycloh ex-1-en yl (c)). These reactions were carried out in the
same manner as described below for 7a with HOTf. Aqueous
HOTf (0.32 mL, 0.90 mmol of H2O containing 35 wt % HOTf)
was added to a solution of 7 (0.3 g, 0.29 mmol) in CHCl3 (15
mL) at 25 °C, and the reaction mixture was stirred for 5 h.
Excess HOTf was removed by washing with H2O. Addition of
n-pentane (10 mL) to the CHCl3 solution resulted in beige
microcrystals of “Ir”, which were removed by filtration. The
filtrate was distilled at 25 °C under vacuum to less than 1.0
mL, and the residue was eluted with n-pentane on a column
packed with silica gel to obtain cis-transoid CH2dCHCHd
CHCtCPh (3a ).
P r ep a r a tion of [Ir (CHdCHCHdCHC(dCH-p-C6H4R′))-
(NCCH3)2(P P h 3)2]BF 4 (19, R′ ) H (a ), CH3 (b)). These
compounds were prepared by the same method as described
below for 19a . To a solution of 17a (0.1 g, 0.1 mmol) and
CH3CN (0.010 g, 0.24 mmol) in CHCl3 (10 mL) was added
Me3NO (0.019 g, 0.25 mmol), and the reaction mixture was
stirred at 25 °C under N2 for 30 min before the reddish solution
Cis-tr a n soid CH2dCHCHdCHCtCP h (3a ). 1H NMR
(500 MHz, CDCl3): δ 7.3-7.5 (m, C6H5, 5H), 7.04 (dt, J (H-H)
) 17.0 Hz, J (H-H) ) 11.0 Hz, Hc), 6.49 (t, J (H-H) ) 11.0

4792 Organometallics, Vol. 21, No. 22, 2002
Chin et al.
Ta ble 1. Deta ils of Cr ysta llogr a p h ic Da ta
Hz, Hd), 5.74 (d, J (H-H) ) 11.0 Hz, He), 5.46 (d, J (H-H) )
17.0 Hz, Hb), 5.37 (d, J (H-H) ) 11.0 Hz, Ha). 13C NMR (126
MHz, CDCl3): δ 140.3 (Cd), 134.1 (Cc), 120.4 (Cb), 109.9 (Ca),
123.3 and 119.8 (CtCPh), 131.5, 128.8, 128.3, and 128.2
(C6H5). HETCOR (1H NMR (500 MHz) f 13C NMR (126
MHz)): δ 7.04 f 134.1; 6.49 f 140.3; 5.74 f 109.9; 5.46
f120.4; 5.37 f 120.4. Electronic absorption: λmax 300, 318 nm.
MS: m/z 154 (M+).
Collection for 9a a a n d 17bb
9a
17b
C50H42BF4IrOP2
1637.89
293(2)
0.44 × 0.40 × 0.10
monoclinic
P21/n
dark orange
17.698(2)
16.6739(19)
20.021(2)
90.00
108.4(2)
90.00
5607.0(11)
5
2.425
4.189
chem formula
fw
C
92H72Ir2O2P4
1717.78
293(2)
0.5 × 0.2 × 0.4
monoclinic
P21/c
deep yellow
12.152(3)
18.888(3)
18.289(3)
90.00
106(2)
90.00
4040.4(14)
2
1.412
temp, K
cryst dimens, mm
cryst syst
space group
color of cryst
a, Å
Cis-tr a n soid CH2dCHCHdCHCtC-p-C6H4CH3 (3b). 1H
NMR (300 MHz, CDCl3): δ 7.4-7.5 (AB quartet with ∆ν/J )
5.6, p-C6H4-CH3, 4H), 7.04 (dt, J (H-H) ) 16.1 Hz, J (H-H)
) 10.5 Hz, Hc), 6.46 (t, J (H-H) ) 10.5 Hz, Hd), 5.74 (d,
J (H-H) ) 10.5 Hz, He), 5.45 (d, J (H-H) ) 16.1 Hz, Hb), 5.36
(d, J (H-H) ) 10.5 Hz, Ha), 2.40 (s, CH3). MS: m/z 168 (M+).
b, Å
c, Å
R, deg.
â, deg.
γ, deg.
Cis-tr an soid CH2dCHCHdCHCtCCdCH(CH2)3CH2 (3c).
1H NMR (300 MHz, CDCl3): δ 6.92 (dt, J (H-H) ) 16.8 Hz,
J (H-H) ) 11.0 Hz, Hc), 6.38 (t, J (H-H) ) 11.0 Hz, Hd), 6.17
V, Å3
Z
F
calcd, g cm-3
µ, mm-1
3.416
1708
(br s, CtCCdCH(CH2)3CH2), 5.63 (d, J (H-H) ) 11.0 Hz, He),
5.37 (d, J (H-H) ) 17.0 Hz, Hb), 5.29 (d, J (H-H) ) 11.0 Hz,
Ha). MS: m/z 158 (M+).
F(000)
4020
radiation
wavelength, Å
2θmax, deg
hkl range
Mo ΚR
Mo ΚR
0.7107
0.7107
40
50
0 e h e 11
0 e k e 18
-17 e l e 16
3768
3768
2501
-21 e h e 21
-18 e k e 20
-24 e l e 24
42 263
10 490
3849
no. of rflns
no. of unique data
no. of obsd (|Fo| >
2σFo) data
no. of params
scan type
R1
216
640
ω scan
0.111
0.315
1.223
ω scan
0.0430
0.1052
0.947
Cisoid CH2dC(CH2)4CdCHCtCP h (5a ). 1H NMR (500
MHz, CDCl3): δ 7.3-7.4 (m, C6H5, 5H), 5.53 (m, Hc), 5.42 (m,
Ha), 5.14 (Hb), 2.32 (m, Hd, 4H), 1.69 (m, He, 4H). 13C NMR
wR2
GOF
R1 ) [∑|Fo| - |Fc|/|Fo|]. wR2 ) [∑w(Fo2 - Fc2)2/∑w (Fo2)2]0.5; w
a
2
2
) 1/[σ2Fo + (0.1037P)2 + 319.7255P], where P ) (Fo + 2Fc2)/3.
(126 MHz, CDCl3): δ 153.1 and 145.2 (both s, CH2dC(CH2)4Cd
CHCtCPh), 112.7 (Ca), 102.3 (Cc), 91.4 and 88.2 (CtC), 36.8
and 36.0 (Cd), 26.93 and 26.90 (Ce). HETCOR (1H NMR (500
MHz) f 13C NMR (126 MHz)): δ 5.53 f 102.3; 5.42, 5.14 f
112.7; 2.32 f 36.8 and 36.0; 1.69 f 26.93 and 29.90. MS: m/z
208 (M+).
R1 ) [∑|Fo| -|Fc|/|Fo|]. wR2 ) [∑w(Fo - Fc2)2/∑w (Fo2)2]0.5; w )
b
2
1/[σ2Fo + (0.0538P)2 + 0.0000P], where P ) (Fo + 2Fc2)/3.
2
2
CCH dC(CH 2)4CdCH 2)2 (12), a n d m ,m -C6H 3(CtCCH d
CHCHdCH2)3 (13). These reactions were carried out in the
same manner as described above for those of 3 with HOTf.
The yields of yellow oils of 11-13 were ca. 85-93% based on
Cisoid CH2dC(CH2)4CdCHCtC-p-C6H4CH3 (5b). 1H NMR
(500 MHz, CDCl3): δ 7.09-7.29 (AB quartet, p-C6H4CH3, ∆ν/J
) 11.6, 4H), 5.52 (m, Hc), 5.42 (m, Ha), 5.14 (m, Hb), 2.34 (s,
p-C6H4CH3, 3H) 2.32 (m, Hd, 4H), 1.68 (m, He, 4H). 13C NMR
1
11-13 measured by H NMR.
p-C6H4(CtCCHdCHCHdCH2)2 (11). 1H NMR (500 MHz,
CDCl3): δ 7.41 (s, C6H4), 6.98 (dt, J (H-H) ) 17.0, J (H-H) )
11.0 Hz, Hc), 6.47 (t, J (H-H) ) 11.0 Hz, Hd), 5.70 (d, J (H-H)
) 11.0 Hz, He), 5.44 (d, J (H-H) ) 17.0 Hz, Hb), 5.35 (d,
J (H-H) ) 11.0 Hz, Ha). 13C NMR (126 MHz, CDCl3): δ 140.7
(Cd), 134.0 (Cc), 131.4 (Ca), 123.2 (C6H4), 120.8 (Cb), 109.6 (Ce),
95.4 and 88.4 (CtCC6H4). HETCOR (1H (500 MHz) f 13C (126
MHz)): δ 7.41 f 131.4; 6.98 f 134.0; 6.47 f 140.7; 5.70 f
109.6; 5.44, 5.35 f 120.8. Electronic absorption: λmax 242, 289,
340, 337 nm. MS: m/z 230 (M+).
(126 MHz, CDCl3): δ 153.5 and 145.2 (both s, CH2dC(CH2)4Cd
CHCtCPh), 112.7 (Ca), 102.4 (Cc), 91.6 and 87.6 (CtC), 36.7
and 36.0 (Cd), 26.93 and 26.90 (Ce). MS: m/z 222 (M+).
Cisoid CH2dC(CH2)4CdCHCtCCdCH(CH2)3CH2 (5c).
1H NMR (300 MHz, CDCl3): δ 6.03 (br s, CtCCdCH-
(CH2)3CH2), 5.41 (s, Hc), 5.32 (s, Ha), 5.07 (m, Hb). MS: m/z
212 (M+).
Cis-tr a n soid CHDdCHCHdCHCtCP h (3a -d ). The 1H
NMR spectrum of the isotopomer cis-transoid CHDdCHCHd
CHCtCPh shows a decreased intensity of the signals due to
CHbDdCHCHdCHCtCPh and CDHadCHCHdCHCtCPh at
δ 5.46 and 5.37 (see Supporting Information). MS: m/z 155
(M+).
p-C6H4(CtCCHdC(CH2)4CdCH2)2 (12). 1H NMR (300
MHz, CDCl3): δ 7.28 (s, p-C6H4, 4H), 5.51 (br s, p-C6H4(Ct
CCHdC(CH2)4CdCH2)2), 5.38 and 5.13 (both br s, p-C6H4-
(-CtCCHdC(CH2)4CdCH2)2, 4H), 2.31 and 1.68 (both m,
p-C6H4(CtCCHdC(CH2)4CdCH2)2, 16H). MS: m/z 338 (M+).
m ,m -C6H3(CtCCHdCHCHdCH2)3 (13). 1H NMR (500
MHz, CDCl3): δ 7.49 (s, C6H3), 6.97 (dt, J (H-H) ) 17.0,
J (H-H) ) 11.0 Hz, Hc), 6.49 (t, J (H-H) ) 11.0 Hz, Hd), 5.68
(d, J (H-H) ) 11.0 Hz, He), 5.45 (d, J (H-H) ) 17.0 Hz, Hb),
5.36 (d, J (H-H) ) 11.0 Hz, Ha). 13C NMR (126 MHz, CDCl3):
δ 141.1 (Cd), 134.0 (Cc), 133.7 (Ca), 124.1 (C6H4), 121.0 (Cb),
109.3 (Ce), 93.9 and 87.5 (CtC). HETCOR (1H (500 MHz) f
13C (126 MHz)): δ 7.49 f 133.7; 6.97 f 134.0; 6.49 f 141.1;
5.68 f 109.3; 5.45, 5.36 f 121.0. Electronic absorption: λmax
) 305, 325 nm. MS (FD): m/z 306 (M+).
Cisoid CHDdC(CH2)4CdCHCtCP h (5a -d ). The 1H NMR
spectrum of the isotopomer cis-transoid CHDdC(CH2)4CHd
CHCtCPh shows the decreased intensity of the signals due
to CHbDdC(CH2)4CdCHCtCPh and CDHadC(CH2)4CdCHCt
CPh at δ 5.42 and 5.14 (see Supporting Information). MS: m/z
209 (M+).
Rea ction s of Di- a n d Tr in u clea r Alk yn yl Ir id a cyclo-
p en ta d ien es 9 a n d 10 w ith HOTf: F or m a tion of Di-
en yn es p -C6H 4(CtCCHdCH CHdCH 2)2 (11), p -C6H 4(Ct

Synthesis of Linear Dienynes from Alkynes
Organometallics, Vol. 21, No. 22, 2002 4793
Rea ction s of 2 w ith RCtCH(D): F or m a tion of Di-
en yn es R CtCCHdCH CHdCH 2 (3) a n d R CtCCHd
X-r a y Str u ctu r e Deter m in a tion of [Ir (-CHdCHCHd
CHC(dCH-p-C6H4CH3))(CO)(P P h 3)2]BF 4 (17b). Crystals of
17b were grown by slow evaporation from CHCl3 solution. The
crystal evaluation and data collection were performed on a
Bruker CCD diffactometer with Mo KR radiation. Preliminary
orientation matrix and cell constants were determined from
three series of ω scans at different starting angles. Each series
consisted of 10 frames collected at intervals of 0.3° ω scans
with an exposure time of 10 s per frame. The structure of this
compound was solved by direct methods from the E map
(SHELXS-97). Non-hydrogen atoms were located in an alter-
nating series of least-squares cycles and difference Fourier
maps. Non-hydrogen atoms were refined with anisotropic
displacement coefficients. All hydrogen atoms were included
in the structure factor calculation at idealized positions and
were allowed to ride on the neighboring atoms with relative
isotropic displacement coefficients. Details of the crystal-
lographic data collection are listed in Table 1. Bond distances
and angles, positional and thermal parameters, and anisotro-
pic thermal parameters have been included in the Supporting
Information.
C(CH2)4CdCH2 (5) a n d Cyclotr im er s RC6H5 (4) a n d
RC6H3C6H8 (6, 6-Ar yl-1,2,3,4-tetr a h yd r on a p h th a len e) (R
) P h , p-C6H4CH3). These reactions were carried out in the
same manner as described below for 2a with PhCtCH. A
CHCl3 (10 mL) solution of 2a (0.30 g, 0.3 mmol) and PhCt
CH (0.1 mL, 0.9 mmol) was stirred at 50 °C for 18 h before
pentane (20 mL) was added to precipitate beige microcrystals
of “Ir -A”, which were collected by filtration, washed with
n-pentane (3 × 10 mL), and dried under vacuum. The ratio of
PhCtCCHdCHCHdCH2 to C6H5C6H5 (biphenyl) was deter-
mined by GC.
Rea ction of “Ir -A” w ith HCtCH a n d HCtC(CH2)4Ct
CH . These reactions were carried out in the same manner
as described below for the reaction of “Ir -A” with HCtCH.
The reaction mixture of “Ir -A” (0.1 g) and NCCH3 (0.03
mL, 0.18 mmol) in CHCl3 solution (10 mL) was stirred under
HCtCH (2 atm) for 24 h in a bomb reactor before n-pen-
tane (20 mL) was added to precipitate beige microcrystals of
2a , which were collected by filtration, washed with n-pen-
tane (3 × 10 mL), and dried under vacuum. The yield was
Ack n ow led gm en t. We wish to thank Prof. M. Choi,
Yonsei University, for X-ray crystal analysis, the Korea
Basic Science Institute for FAB-mass measurements,
and the Korea Science and Engineering Foundation
(Grant No. R01-2000-00044) for financial support of this
study.
0.07 g (82%) based on [Ir(CHdCHCHdCH)(CO)(NCCH3)-
(PPh3)2]OTf (2a ).
X-r a y St r u ct u r e Det er m in a t ion of p -C6H 4(Ct
CIr (-CHdCHCHdCH)L3)2 (9a , L ) (CO)(P P h 3)2). Crystals
of 9a were grown by slow evaporation from CH2Cl2 solution.
Diffraction data were collected on an Enraf-Nonius CAD4
diffractometer with graphite-monochromated Mo KR radiation
at 20 °C. All data were collected with the ω scan modes and
corrected Lp effects and absorption. The structure of this
compound was solved by Patterson’s heavy-atom methods
(SHELXS-97). In the least-squares refinement, six non-H
atoms were refined anisotropically, all 92 C atoms were refined
isotropically, and all hydrogen atoms were placed at their
geometrically calculated positions with isotropic thermal
parameters. Details of the crystallographic data collection are
listed in Table 1. Bond distances and angles, positional and
thermal parameters, and anisotropic thermal parameters have
been included in the Supporting Information.
Su p p or tin g In for m a tion Ava ila ble: Tables of bond
distances and angles, positional and thermal parameters, and
anisotropic thermal parameters for complexes 9a and 17b in
CIF format and figures giving 1H and 13C NMR and HETCOR
(1H-13C) spectra of complexes 8a , 8b, 9b, 10, 17b, 18b, and
19b, 1H NOE spectra of 17b and 19a , FAB mass data of 9a
and 10, 1H NMR spectra and mass data of organic compounds
1
3a , 5a , 11, and 13, 1H NOE of 3a and 5a , and H NMR spectra
of 3a -d and 5a -d . This material is available free of charge via
the Internet at http://pubs.acs.org.
OM020493B