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Can. J. Chem. Vol. 82, 2004
(EI): 842 (M – 1CO)+, 786 (M – 3CO)+. (LSI-MS) m/e 767
dry THF (20 mL) was added 3-menthyloxy-1-propyne (14)
(1.464 g, 7.53 mmol) in a cannula under a stream of nitro-
gen. The solution was heated for 30 min at 60 °C and cooled
to room temperature. CuCl was added (74 mg, 0.75 mmol),
followed by propargyl bromide (1.67 mL, 18.0 mmol). The
solution was heated to reflux for 1 h. A conventional
workup and subsequent flash chromatography (100% hex-
ane) afforded (15) (1.313 g, 75%) as a colorless oil. [α]D25
–66.9 (c 1.17 acetone). IR (neat) (cm–1) νmax: 3312, 2954,
(M – 3CO)+, 730 (M – 5CO)+.
Dodecacarbonyl[4 -(,,,)(1-(1-carboethoxycyclo-
hexyl)dec-9-ene-2,5-diyne)]tetracobalt (2 Co-Co) (10b)
Compound 8c (109.8 mg, 0.119 mmol) was reacted with
allyltrimethylsilane (38 µL, 0.24 mmol) and BF3-OEt2
(30 µL, 0.24 mmol) via the standard procedure. Flash chro-
matography (petroleum ether:diethyl ether, 25:1) afforded
1
10b (77.6 mg, 76%), as a red-brown oil. IR (neat, KBr) (cm–1)
2869. H NMR δ: 4.16 (t of 1/2AB, J = 2.0, 15.5, 1H), 4.11
1
(t of 1/2AB, J = 1.9, 15.5, 1H), 3.16 (m, 3H), 2.18 (m, 1H),
2.03 (m, 1H), 1.57 (m, 2H), 1.57 (m, 1H), 1.34 (m,1H),
0.70–1.00 (m, 4H), 0.87 (d, J = 6.6, 3H), 0.84 (d, J = 7.1,
3H), 0.74 (d, J = 6.9, 3H). 13C NMR δ: 78.5, 77.78, 77.74,
77.72, 68.8, 55.4, 48.0, 39.7, 34.3, 31.3, 25.2, 23.1, 22.2,
20.9, 16.0, 9.5. MS (EI) m/e: 232 (M)+. HR-MS calcd. for
C16H24O: 232.1827; found: 232.1826.
ν
max: 2094, 2084, 2048, 2014, 1728. H NMR δ: 5.95 (m,
1H), 5.17 (d, J = 17.1, 1H), 5.10 (d, J = 10.3, 1H), 4.60 (s,
2H), 4.21 (q, J = 7.1, 2H), 3.27 (s, 2H), 2.95–3.05 (m, 2H),
2.38–2.50 (m, 2H), 2.12–2.30 (m, 2H), 1.20–1.75 (m, 8H),
1.28 (t, J = 7.1, 3H). 13C NMR δ: 199.9, 199.8, 175.4, 136.8,
115.8, 98.5, 95.2, 92.8, 92.6, 60.6, 48.1, 43.8, 41.2, 35.6,
34.6, 32.5, 29.7, 25.6, 22.8, 14.0. MS (EI): 774 (M – 3CO)+,
718 (M – 5CO)+. (LSI-MS) m/e: 774 (M – 3CO)+, 718 (M –
5CO)+, 690 (M – 6CO)+.
(1′R, 2′S, 5′R)- Dodecacarbonyl[4 -(,,,)(1-menthoxy-
7-methoxy-2,5-heptadiyne)]tetracobalt (2 Co-Co) (16)
To a solution of 15 (1.75 g, 7.50 mmol) in diethyl ether
(20 mL) at –78 °C was added MeLi (8.0 mL, 1.40 mol L–1,
11.2 mmol). The solution was then stirred for 20 min, and
chloromethyl methyl ether (1.13 mL, 15.0 mmol) was added.
The reaction mixture was allowed to warm up to room tem-
perature and stirred overnight. Following a conventional
workup, the resulting crude product was dissolved in anhyd.
Et2O (20 mL) and cooled to 0 °C. An excess of cobalt car-
bonyl was added and the solution stirred for 3.5 h. The re-
sulting crude product was filtered though Celite®, and the
resulting filtrate was concentrated under reduced pressure.
Flash chromatography (petroleum ether:diethyl ether, 50:1)
gave 16 (3.946 g, 72%) as a red-brown oil. [α]2D2 +72 (c
Synthesis of dodecacarbonyl[4 -(,,,)(1-benzyloxy-7-
hydroxy-2,5-undecadiyne)]tetracobalt (2 Co-Co) (11)
To a solution of freshly prepared 6-benzyloxy-1,4-
hexadiyne (4) (56.4 mg, 3.06 mmol) in THF at –78 °C was
added methyllithium (3.06 mL, 1.5 mol L–1, 4.59 mmol).
The mixture was stirred for 20 min and freshly distilled
pentanal (651 µL, 6.12 mmol) was added dropwise. After
stirring for 3 h, the reaction mixture diluted with cold water
at 0 °C. Following a conventional workup, the crude product
was diluted with diethyl ether and placed in an ice bath. An
excess amount of cobalt carbonyl was added and the mixture
stirred for 3.5 h. Following removal of the volatiles under re-
duced pressure, flash chromatography (petroleum ether:di-
ethyl ether, 20:1) gave (11) (90.2 mg, 44%) as a red-brown
1
0.036 acetone). IR (neat) (cm–1) νmax: 2923, 2052. H NMR
1
oil. IR (neat) (cm–1) νmax: 3386, 2919, 2012. H NMR δ:
δ: 4.8 (d, J = 12.5, 1H), 4.6 (m, 4H), 4.51 (d, J = 12.5, 1H),
3.52 (s, 3H), 3.26 (apparent dt, J = 4.1, 10.5, 1H), 2.31 (m,
1H), 2.14 (d, J = 12.0, 1H), 1.67 (m, 2H), 1.41 (m, 1H), 1.31
(m, 1H), 0.88–1.10 (m, 3H), 0.96 (d, J = 6.0, 3H), 0.90 (d,
J = 7.0, 3H), 0.80 (d, J = 6.9, 3H). 13C NMR δ: 199.7, 94.7,
92.7, 91.6, 90.7, 79.3, 72.6, 67.8, 58.8, 48.2, 41.0, 40.3,
34.5, 31.6, 25.3, 23.1, 22.3, 20.8, 15.9. MS (EI) m/e: 820
(M – CO)+, 596 (M – 9CO)+. MS (ES+) m/e: 691 (M + K –
7CO)+.
7.32 (m, 5H), 4.68 (m, 7H), 2.79 (d, J = 5.2, 1H), 1.64 (m,
3H), 1.36 (m, 3H), 0.92 (t, J = 7.1, 3H). 13C NMR δ: 199.6,
199.3, 137.0, 128.5, 128.1, 128.0, 102.4, 92.0, 91.3, 91.0,
73.4, 71.5, 70.1, 41.2, 39.2, 28.5, 22.4, 13.9. MS (EI) m/e:
758 (M – 3CO)+, 618 (M – 8CO)+. (LSI-MS) m/e: 757 (M –
1 – 3CO)+, 617 (M – 1 – 8CO)+.
Dodecacarbonyl[4 -(,,,)(1-benzyloxy-2,5-
undecadiyne)]tetracobalt (2 Co-Co) (13)
(1′R, 2′S, 5′R)- Dodecacarbonyl[4 -(,,,)(1-menthoxy-
dec-9-ene-2,5-diyne)]tetracobalt (2 Co-Co) (18a)
To a solution of (11) (353 mg, 0.41 mmol) and Ph3SnH
(220 mg, 0.62 mmol) in CH2Cl2 (10 mL) at 5 °C was added
BF3-Et2O (53 µL, 0.41 mmol). After stirring for 20 h with
regular monitoring by TLC, the reaction mixture was diluted
with water and subjected to conventional workup. Flash
chromatography (petroleum ether:diethyl ether, 100:1) af-
forded (13) as a red-brown oil (290 mg, 84%). IR (neat)
To a solution of 16 (207 mg, 0.244 mmol) in CH2Cl2
(5 mL) at 0 °C was added BF3·Et2O (144 µL, 1.14 mmol).
The solution stirred for 10 min; thereafter, allyltrimethy-
silane (67 µL, 0.42 mmol) was added and the reaction was
continued until none of the starting 16 was detected in TLC
analysis (12 h). A conventional workup and subsequent flash
chromatography (100% petroleum ether) afforded 18a
(148 mg, 71%) as a red-brown oil. [α]2D2 +52 (c 0.079 ace-
1
(cm–1) νmax: 2933, 2099. H NMR δ: 7.35 (m, 5H), 4.74 (s,
2H), 4.70 (s, 2H), 4.65 (s, 2H), 2.84 (t, J = 8.0, 2H), 1.66
(m, 2H), 1.41 (m, 4H), 0.95 (t, J = 7.0, 3H). 13C NMR δ:
200.0, 199.5, 137.8, 128.3, 127.7, 127.4, 99.7, 93.0, 92.5,
91.1, 73.0, 69.7, 41.2, 33.3, 31.6, 31.5, 22.3, 13.8. MS (EI)
m/e: 742 (M – 3CO)+, 658 (M – 6CO)+. MS (ES–) m/e:
768.5 (M – 2CO-H)–, 740.5 (M – 3CO-H)–.
1
tone). IR (neat) (cm–1) νmax: 2924, 2085, 2049. H NMR δ:
5.94 (m, 1H), 5.17 (d, J = 17.0, 1H), 5.10 (d, J = 12.1, 1H),
4.82 (d, J = 12.4, 1H), 4.65 (s, 2H), 4.50 (d, J = 12.4, 1H),
3.24 (apparent dt, J = 4.0, 10.5, 1H), 2.99 (m, 2H), 2.42 (m,
2H), 2.29 (m, 1H), 2.11 (br d, J = 12.1 1H), 1.63 (m, 2H),
1.30 (m, 1H), 1.28 (m, 1H), 0.85–1.17 (m, 3H), 0.95 (d, J =
6.4, 3H), 0.89 (d, J = 7.0, 3H), 0.78 (d, J = 7.0, 3H). 13C
(1′R, 2′S, 5′R)- 1-Menthoxy-2,5-heptadiyne (15)
To a freshly prepared solution of EtMgBr (15.0 mmol) in
© 2004 NRC Canada