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Regioselective joining of prenyl units. A simple strategy for geometry control in Pd catalyzed allylic alkylations
‘kuahedron Lettm, Vo1.32, No.20. pp 2193-2196.1991 Printed in Great Britain
O(MO4039191 %3.00+ .w Pcrgamm Press plc
Regioselective Joining of Prenyl Units. A Simple Strategy for Geometry Control in Pd Catalyzed Allylic Alkylations
Barry M. Trost* and Juan K. Granjaf Department of chemistry Stanford University Stanford, CA g&035-5060
Summary: Either E,E-3,9-dimethylundecadien-l,ll-dial or its E,Z-isomer is selectively available via Pd catalyzed allyllc alkylaLion as a function of alkylating agent and catalyst - an observation that establishes that reactions of vinyl epoxides and their related vinyl carbonates do not proceed through a common intermediate. The recent emergence of an insect pheromonelo regioaelective jninIng
of two
prenyl units
to a
which
can
C-l unit
be
viewed
induced us
as
arising by
to develop such a
coupling hased upon a lynchpin strategy using neutral alkylations according to eq. 1.3
We
PhSOz PhS4 >
1 wish
to
2
3 record the unusual effects of leaving group on
olefin
4 and of experimental
geometry
parameters for mono- versus di-alkylation. These results also provide
mechanistic insight:
into the reactions of vinyl carborlates 4 as electrophiles in ~~allylpalladium chemistry. Exposure
of
bis(ben2erteuul~onyl)methnnp1
and
catalysts led cleanly to the monoalkylatcd products 5a
reaction times,
vinyl
and
with
6
epoxide no
Z5 to Pd(O)
dialkylation even
7 a)X=O, b)x-c0&
a)R=H. b)R=Th!S,c)R=TBDMS after prolonged
excess
8
As expecred, the E isomer dominated with some dependence
on catalyst [4.?:1 with (dba)3Pd2
CHC13, dppe, THF, rt. 66%; 9.7:1 with (Ph3P)qPd, dppp.
THF, rt-,77%]. The high
reactivity of
speculate that the failure of uansfer
the vinyl the
epoxide 2
second
towards the
alkylation lay
in
Pd(0) complexes led us to the
from the monoalkylated 5a to the reactive intermediate ?a.
of the vIny1 + Spanish
epoxide
thca
prevented
Mirlistry nf Education
its
being
and Science 7107
effectively
Postdoctoral
more
captured, Fellow
sluggish proton
The self decomposition Believing
that
-
2194
alkoxirlein 7a would prolong the lifetime of the reactive intermediate led
stabilizing the
us to investigate alkylations with the epoxide.
vinyl carbonate 8, a
synthetic equivalent of the
The latter was readily derived from the epoxide 2 using Pd(0) catalysts 12 atm
COP, 3 ml% Pd(OAc)z, 22 mol% ciC3H70)3P, THF, rt, 85~1.~
The reaction still refused to go
beyond monnalkylstion upon subjecting the bis-sulforleI to an excess of cyclic carbonate 8 in the presence of Pd(0) catalysts. Surprisingly, the major geometrical isomer was the Zolefin
6
[Pd(OAc)2, (iC3H70)3F, THF,
70'.
vinylepoxidc 2 to a prnnucleophile Leads to
a
78%,
1~1.2
E:Z].
preference for
the
Thus, addition of the E-olefin product but
condensation with the carbonate 8 leads to a preference for the Z-isomer of the product-. The second alkylation dramatically demonstrates this phenomenon. The initial failures to effect the second alkylation apparently stemmed from group since
the silylated monoalkylated products
the presence
5b or
of a
free hydroxyl
5c smoothly participated in the
second alkylation. For example, condensation of Sb with the vinyl carbonate 8 led to a 1:8 mixture of rhe E,E and F.,Zisomers 3 and 9 in 58% yield
(eq. 2).
Use of the TBBMS ether of
(2)
c)R=TBDMS 5 (i.e. 5c) gave the E,Z isomer 9c exclusively in 85% yield!
performed in
a single
operation from
the epoxidc 2.
The reaction was conveniently
A 0.5 M solution of the epoxide and
catalyst derived from 2 mol% Pd(DAc)2 and 15 mol.% (iC3H7C)TP in THF was expnsed to CO2 at 2 atm at
rtfor
4h.
After release of the pressure, the his-sulfone 5c and BSA were added
and the reaction heated at 70° for 1.5 h.
Standard work-up gave t-heproduct 9c.'
Alternatively, exposing 5a or 5b to the vinyl epoxide 2 in the Pd(0) catalyst gave the
presence of
E,E-diene 3 as the major product after desilylation upon work-up.
The formation of 3 was conveniently performed in a single operation from if BSA
is added
after the
first stage.
ct.
BSA and
the his-sulfone 1
Thus, a l.l:l mixture of the vinylepoxidc 2 and
his-surfone 1 in THF containing 5 mol% of (dha)gPd2 h at
BSA and a
CHC13 and 22 mol% dppe was
stirred 2
a second portion (1.2 eq) of vinyl epoxide were added and the reaction
mixture warmed to 7Oo. Work-up followed by recrystallization (ethyl acetate) gave the pure E,E-fs~mer 3,? mp 126-8o, in 74% yield in addition to 17% of the E,Z isomer 9. NMR spectroscopy clearly reveals the nature of the olefln geometry.
lH decoupled 13C
nmr spectroscopy' shows only 9 peaks for the product from the vinyl epoxide alkylation fact that
indicates the
. a
symmetrical nature of the product. The appearance of the signals
21%
was desulfonylated using buffered provide the
desired tail,
tail
soditrmamal.gamLD [6% Na(Hg).
joined
producr 4
in 95%
Na2HP04, CH30H,
yield.
-10'1 to
Thus, a simple
Tetrahedron Lett. 1988, 29, 6561. Eattiste, M.A.; Rocca, J.R.; Wydra, R.L.; Tumlinson, J.H.; Chuman. T. Tetrahedron Lett. 1988, 29, 6565; Mori, K.; Nakazono, Y. Annalen 1988, 167. Trost, B.M.; Malander, G.A.; J. Am. Chem. Sot. 1981, 103, 5969; Tsuji, J.; Kataoka, H.; Knhayashi, Y. Tetrahedron Lett. 1981, 22, 2575; For see Tsuji, J. a review Tetrahedron 1986, 42, 4361. Masse, G.. research support, University of WTsconsin, March 1979; Tsuji, J.; Minami, I. Accounrs Chem. Res. 1987, 2Q, 140. Savu, P.M.; Katzenellenbogen. J.A. .J.Org. C11em.1981, L6, 239; Fujisawa, T.; Sato, T.; Kawara, T.: OhasL, K. Tetrahedron Lett. 1981, 22, 4823. We found it convenient co ore a modification of the latter sequence employing methylthiomethyllithium, alkylation with trimethyloxonlum fluoroborate followed by sodium hydride, cf Tanis, S.P.; McMills, M.C.; Herrinton. P.M. J. Org. Cbem. 1985, 50, 5887. Trust, B.M.; Angle, S.R. J. Am. Chem. Snc. 1985, 107, 6123; Fujinami, T.; Suzuki, T.; Kamija, M.; Fukuzawa, S.; Sakai, S. Chem. Lerr. 1985, 194. 3 IR{KBr): 3433, 1656, 1447, 1334cm.-1 LH NMR(~OOMHZ, CDC13): 68.02 (dd, J-7.4, 1,3Hz, 4H). 7.69 (t, J-7.4Hz, 2H), 7.56 (T, J-7.4Hr, 4H 5.72 (tq, J-6.5, l.lHz, ZH), 4.13 (d, J-6.0Hz, 4H), 3.19 (a, 4H), 1.68 (bs, 6H). ilC NMR(XOOMHz, CDC13): 6137.8, 134.6, 131.8. 131.0, 128.5, 93.7, 59.1, 39.3, 18.2. Anal. C,H,S. 9c IR(CDCl3): 3612, 3540, 1658, 1602, 1584, 1474, 1448, 7397, 1333~11.‘~ 'H NMR(400Mtlz,CDC13): 68.06 (d, J-B.OHz, 4H), 7.72 (t, J-6.4H2, lH), 7.70 (t. J-6.4Hz, lH), 1.60 (d, J-7.6112,2t1),7.58 (d. J-7.6Hz, ZH), 5.77 (bt, J-6.6Hz. LH), 5.67 (bt, J-7.7Hz, lH), 4.3.6 (d, J-6.6Hz, 2H), 4.11 (d, J-7.7H2, 2H), 3.30 (s, 2H), 3.18 (s, ZH), 1.7G (bs, 3H). 1.63 (hs, 3H). 1% NMR(100MHz, CDC13): 6137.7, 134.8, 133.5, 132.8. 132.1, 131.9, 131.3. 128.7, 53.9, 59.?, 58.8, 41.0, 31.7, 25.5, 18.5. Anal. C,H,S. 4 IR(CDC13): 3614, 3442, 1667, 1443, 1384, 1353cm.-L $1 NMR(400MHz, CDCL3): 55.40 it, .I-h.RH;37H), 4.15 (d, J-6.8Hz, 4H), 2.00 (t, J-7.6Hz, AH). 1.66 (a, 6H), 1.52 (m. 2H). Calc'd for C NMR(lOOMHz, CDC13): 6139.4, 123.5, 59.3, 39.0, 25.4, 16.1. ClLHl7(M-H2C'-OH):149.137(1. Found: 149.1318. Trost, B.M.; Hurnaus, R. Tcrrahedron Lett. 1989, 30, 2893; Hayashi, T.; Hagihara, T.; Konishi, M.; Kumada, M. J. Am. Chem. Sot. 1983, 105, 7767; Trost. 3.M.; Verhoeven, Am. Chem. T.R. .I. sot. 1980, 102, 4730: Trost, B.M.; Verhoeven, T.R. J. Org. &am. 1976, 41, 3215. Cf. Trosc, B.M.; Schmuff, N.R.; Miller, M.J. J. Am. Chem. Sot. 1980. 102, 5979; Inomata, K.; Murata, Y.; Kate, H.; Tsukahara, Y.; Kinoshita, H.; Kotake, H. Chem. Lett.1985, 931. Treat, B.M.; Arndt, H.C.; Strcge, P.E.; Verhoeven, T.R. Tetrahedron Letc. 1976, 3477.
(ReceivedinUSA 3 December 1990)
O(MO4039191 %3.00+ .w Pcrgamm Press plc
Regioselective Joining of Prenyl Units. A Simple Strategy for Geometry Control in Pd Catalyzed Allylic Alkylations
Barry M. Trost* and Juan K. Granjaf Department of chemistry Stanford University Stanford, CA g&035-5060
Summary: Either E,E-3,9-dimethylundecadien-l,ll-dial or its E,Z-isomer is selectively available via Pd catalyzed allyllc alkylaLion as a function of alkylating agent and catalyst - an observation that establishes that reactions of vinyl epoxides and their related vinyl carbonates do not proceed through a common intermediate. The recent emergence of an insect pheromonelo regioaelective jninIng
of two
prenyl units
to a
which
can
C-l unit
be
viewed
induced us
as
arising by
to develop such a
coupling hased upon a lynchpin strategy using neutral alkylations according to eq. 1.3
We
PhSOz PhS4 >
1 wish
to
2
3 record the unusual effects of leaving group on
olefin
4 and of experimental
geometry
parameters for mono- versus di-alkylation. These results also provide
mechanistic insight:
into the reactions of vinyl carborlates 4 as electrophiles in ~~allylpalladium chemistry. Exposure
of
bis(ben2erteuul~onyl)methnnp1
and
catalysts led cleanly to the monoalkylatcd products 5a
reaction times,
vinyl
and
with
6
epoxide no
Z5 to Pd(O)
dialkylation even
7 a)X=O, b)x-c0&
a)R=H. b)R=Th!S,c)R=TBDMS after prolonged
excess
8
As expecred, the E isomer dominated with some dependence
on catalyst [4.?:1 with (dba)3Pd2
CHC13, dppe, THF, rt. 66%; 9.7:1 with (Ph3P)qPd, dppp.
THF, rt-,77%]. The high
reactivity of
speculate that the failure of uansfer
the vinyl the
epoxide 2
second
towards the
alkylation lay
in
Pd(0) complexes led us to the
from the monoalkylated 5a to the reactive intermediate ?a.
of the vIny1 + Spanish
epoxide
thca
prevented
Mirlistry nf Education
its
being
and Science 7107
effectively
Postdoctoral
more
captured, Fellow
sluggish proton
The self decomposition Believing
that
-
2194
alkoxirlein 7a would prolong the lifetime of the reactive intermediate led
stabilizing the
us to investigate alkylations with the epoxide.
vinyl carbonate 8, a
synthetic equivalent of the
The latter was readily derived from the epoxide 2 using Pd(0) catalysts 12 atm
COP, 3 ml% Pd(OAc)z, 22 mol% ciC3H70)3P, THF, rt, 85~1.~
The reaction still refused to go
beyond monnalkylstion upon subjecting the bis-sulforleI to an excess of cyclic carbonate 8 in the presence of Pd(0) catalysts. Surprisingly, the major geometrical isomer was the Zolefin
6
[Pd(OAc)2, (iC3H70)3F, THF,
70'.
vinylepoxidc 2 to a prnnucleophile Leads to
a
78%,
1~1.2
E:Z].
preference for
the
Thus, addition of the E-olefin product but
condensation with the carbonate 8 leads to a preference for the Z-isomer of the product-. The second alkylation dramatically demonstrates this phenomenon. The initial failures to effect the second alkylation apparently stemmed from group since
the silylated monoalkylated products
the presence
5b or
of a
free hydroxyl
5c smoothly participated in the
second alkylation. For example, condensation of Sb with the vinyl carbonate 8 led to a 1:8 mixture of rhe E,E and F.,Zisomers 3 and 9 in 58% yield
(eq. 2).
Use of the TBBMS ether of
(2)
c)R=TBDMS 5 (i.e. 5c) gave the E,Z isomer 9c exclusively in 85% yield!
performed in
a single
operation from
the epoxidc 2.
The reaction was conveniently
A 0.5 M solution of the epoxide and
catalyst derived from 2 mol% Pd(DAc)2 and 15 mol.% (iC3H7C)TP in THF was expnsed to CO2 at 2 atm at
rtfor
4h.
After release of the pressure, the his-sulfone 5c and BSA were added
and the reaction heated at 70° for 1.5 h.
Standard work-up gave t-heproduct 9c.'
Alternatively, exposing 5a or 5b to the vinyl epoxide 2 in the Pd(0) catalyst gave the
presence of
E,E-diene 3 as the major product after desilylation upon work-up.
The formation of 3 was conveniently performed in a single operation from if BSA
is added
after the
first stage.
ct.
BSA and
the his-sulfone 1
Thus, a l.l:l mixture of the vinylepoxidc 2 and
his-surfone 1 in THF containing 5 mol% of (dha)gPd2 h at
BSA and a
CHC13 and 22 mol% dppe was
stirred 2
a second portion (1.2 eq) of vinyl epoxide were added and the reaction
mixture warmed to 7Oo. Work-up followed by recrystallization (ethyl acetate) gave the pure E,E-fs~mer 3,? mp 126-8o, in 74% yield in addition to 17% of the E,Z isomer 9. NMR spectroscopy clearly reveals the nature of the olefln geometry.
lH decoupled 13C
nmr spectroscopy' shows only 9 peaks for the product from the vinyl epoxide alkylation fact that
indicates the
. a
symmetrical nature of the product. The appearance of the signals
21%
was desulfonylated using buffered provide the
desired tail,
tail
soditrmamal.gamLD [6% Na(Hg).
joined
producr 4
in 95%
Na2HP04, CH30H,
yield.
-10'1 to
Thus, a simple
Tetrahedron Lett. 1988, 29, 6561. Eattiste, M.A.; Rocca, J.R.; Wydra, R.L.; Tumlinson, J.H.; Chuman. T. Tetrahedron Lett. 1988, 29, 6565; Mori, K.; Nakazono, Y. Annalen 1988, 167. Trost, B.M.; Malander, G.A.; J. Am. Chem. Sot. 1981, 103, 5969; Tsuji, J.; Kataoka, H.; Knhayashi, Y. Tetrahedron Lett. 1981, 22, 2575; For see Tsuji, J. a review Tetrahedron 1986, 42, 4361. Masse, G.. research support, University of WTsconsin, March 1979; Tsuji, J.; Minami, I. Accounrs Chem. Res. 1987, 2Q, 140. Savu, P.M.; Katzenellenbogen. J.A. .J.Org. C11em.1981, L6, 239; Fujisawa, T.; Sato, T.; Kawara, T.: OhasL, K. Tetrahedron Lett. 1981, 22, 4823. We found it convenient co ore a modification of the latter sequence employing methylthiomethyllithium, alkylation with trimethyloxonlum fluoroborate followed by sodium hydride, cf Tanis, S.P.; McMills, M.C.; Herrinton. P.M. J. Org. Cbem. 1985, 50, 5887. Trust, B.M.; Angle, S.R. J. Am. Chem. Snc. 1985, 107, 6123; Fujinami, T.; Suzuki, T.; Kamija, M.; Fukuzawa, S.; Sakai, S. Chem. Lerr. 1985, 194. 3 IR{KBr): 3433, 1656, 1447, 1334cm.-1 LH NMR(~OOMHZ, CDC13): 68.02 (dd, J-7.4, 1,3Hz, 4H). 7.69 (t, J-7.4Hz, 2H), 7.56 (T, J-7.4Hr, 4H 5.72 (tq, J-6.5, l.lHz, ZH), 4.13 (d, J-6.0Hz, 4H), 3.19 (a, 4H), 1.68 (bs, 6H). ilC NMR(XOOMHz, CDC13): 6137.8, 134.6, 131.8. 131.0, 128.5, 93.7, 59.1, 39.3, 18.2. Anal. C,H,S. 9c IR(CDCl3): 3612, 3540, 1658, 1602, 1584, 1474, 1448, 7397, 1333~11.‘~ 'H NMR(400Mtlz,CDC13): 68.06 (d, J-B.OHz, 4H), 7.72 (t, J-6.4H2, lH), 7.70 (t. J-6.4Hz, lH), 1.60 (d, J-7.6112,2t1),7.58 (d. J-7.6Hz, ZH), 5.77 (bt, J-6.6Hz. LH), 5.67 (bt, J-7.7Hz, lH), 4.3.6 (d, J-6.6Hz, 2H), 4.11 (d, J-7.7H2, 2H), 3.30 (s, 2H), 3.18 (s, ZH), 1.7G (bs, 3H). 1.63 (hs, 3H). 1% NMR(100MHz, CDC13): 6137.7, 134.8, 133.5, 132.8. 132.1, 131.9, 131.3. 128.7, 53.9, 59.?, 58.8, 41.0, 31.7, 25.5, 18.5. Anal. C,H,S. 4 IR(CDC13): 3614, 3442, 1667, 1443, 1384, 1353cm.-L $1 NMR(400MHz, CDCL3): 55.40 it, .I-h.RH;37H), 4.15 (d, J-6.8Hz, 4H), 2.00 (t, J-7.6Hz, AH). 1.66 (a, 6H), 1.52 (m. 2H). Calc'd for C NMR(lOOMHz, CDC13): 6139.4, 123.5, 59.3, 39.0, 25.4, 16.1. ClLHl7(M-H2C'-OH):149.137(1. Found: 149.1318. Trost, B.M.; Hurnaus, R. Tcrrahedron Lett. 1989, 30, 2893; Hayashi, T.; Hagihara, T.; Konishi, M.; Kumada, M. J. Am. Chem. Sot. 1983, 105, 7767; Trost. 3.M.; Verhoeven, Am. Chem. T.R. .I. sot. 1980, 102, 4730: Trost, B.M.; Verhoeven, T.R. J. Org. &am. 1976, 41, 3215. Cf. Trosc, B.M.; Schmuff, N.R.; Miller, M.J. J. Am. Chem. Sot. 1980. 102, 5979; Inomata, K.; Murata, Y.; Kate, H.; Tsukahara, Y.; Kinoshita, H.; Kotake, H. Chem. Lett.1985, 931. Treat, B.M.; Arndt, H.C.; Strcge, P.E.; Verhoeven, T.R. Tetrahedron Letc. 1976, 3477.
(ReceivedinUSA 3 December 1990)