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PRIMARY ALCOHOLS FROM TERMINAL OLEFINS: FORMAL ANTI-MARKOVNIKOV HYDRATION VIA TRIPLE RELAY CATALYSIS Guangbin Dong, Peili Teo , Zachary K. Wickens , Robert H. Grubbs Science 2011 , 333 , 1609. Shawn K. Collins Universit é de Montr é al Department of Chemistry - PowerPoint PPT Presentation
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PRIMARY ALCOHOLS FROM TERMINAL PRIMARY ALCOHOLS FROM TERMINAL OLEFINS: FORMAL ANTI-OLEFINS: FORMAL ANTI-
MARKOVNIKOV HYDRATION VIA MARKOVNIKOV HYDRATION VIA TRIPLE RELAY CATALYSISTRIPLE RELAY CATALYSIS
Guangbin Dong, Peili Teo, Zachary K. Wickens, Robert H. Grubbs Science 2011, 333, 1609.
Shawn K. CollinsShawn K. CollinsUniversitUniversitéé de Montr de Montrééalal
Department of ChemistryDepartment of ChemistryCentre for Green Chemistry and CatalysisCentre for Green Chemistry and Catalysis
[email protected]: Web: http://www.mapageweb.umontreal.ca/collinss/
CHARETTE/COLLINS LITERATURE MEETINGCHARETTE/COLLINS LITERATURE MEETINGUniversité de Montréal (UdeM)Université de Montréal (UdeM)
March 12March 12thth, 2014, 2014Montréal, QuébecMontréal, Québec
1.
2. NaOH, H2O2
OHOB
OH
11.5 : 1 selectivity for primary olef ins
Boron-containing wastes sometimes dif f icult to removeHydrogen peroxide poses problems upon scale-up
OH
H2O
Catalyst
STOICHIOMETRIC SYNTHESIS OF PRIMARY ALCOHOLS
Brown, H. C.; Gupta, S. K. J. Am. Chem. Soc. 1975, 97, 5249.
CATALYTIC SYNTHESIS OF PRIMARY ALCOHOLS
trans-PtHCl(PMe3)2NaOH
H2O: 1-hexene (1:1)60 C, BnEt3NCl
OH
6.9 turnovers/ h
Jensen, C. M.; Trogler, W. C. Science 1986, 233, 1069.
Later proved to “difficult to reproduce”• Marsella and co-workers prepared analytically pure “active” species and proved
it to be inactive
Ramprasad, D.; Yue, H. J.; Marsella, J. A. Inorg. Chem. 1988, 27, 3151.
HO
88 %
HO25 C, 12 h, C6D6
(TPP)RhH KOtBu
25 C, 1 hC6D6
O HO
71 %29 %
Rh(TPP) OH
Sanford, M. S.; Groves, J. T. Angew. Chem. Int. Ed. 2004, 43, 588 .
• Demonstrated each step of a catalytic cycle, but never completed the cycle!
CATALYTIC SYNTHESIS OF PRIMARY ALCOHOLS
One step reaction, but would require an additional saponification and hydrogenation.
81 %
O2 (1 atm), AcOH, 80 C, 18 h
Pd(OAc)2 (5 mol %)
N N
O
(5 mol %)OAc
Campbell, A. N.; White, P. B.; Guzei, I. A.; Stahl, S. S. J. Am. Chem. Soc. 2010, 132, 15116.
Stewart, I. C.; Bergman, R. G.; Toste, F. D. J. Am. Chem. Soc. 2003, 125, 8696.
95 %MeOH, 45 C, 6 h
PMe3 (5 mol %)
O O
OMe
Other work uses “activated” olefins…in this paper they comment that the hydration equivalent is an unknown transformation for organic synthetic
chemists….
Boersma, A. J.; Coquie`re, D.; Geerdink, D.; Rosati, F.; Feringa, B. L.; Roelfes, G. Nature Chem. 2010, 2, 991.
Using Cu catalysis and DNA…Feringa and co-workers finally accomplished this in 2010…
[M] H
R
O
R
O
H
[M]
[M] Cl
H-Cl
R
HO
PROPOSED CATALYTIC RELAY
PdCl2
R
R
PdCl Cl
H2O
RClPd
OH
R
OHClPd
trans hydroxy-palladation (external attack of water)
cis hydroxy-palladation (syn delivery of hydroxide)
or
R
PdH Cl
OH
R
Ovs.
R
O
H-Cl
[O]
Challenges include:•How to get aldehyde selectivity in the Wacker Oxidation (particularly for styrene
derivatives)• Which metal complex could participate in the reduction, and under aqueous
conditions?
WACKER OXIDATION
PdCl2 (12 mol %)H4[PMo11VO40] (1.2 eq.)
DMF:H2O (10:1), 18 h75%
O
O
+
6.4 : 1 selectivity
OH
PdL
L
f avored vs.
PdL
LOH
Wright, J. A.; Gaunt, M. J.; Spencer, J. B. Chem.-Eur. J. 2006, 12, 949.
PdCl2(MeCN)2 (20 mol %)CuCl2 (30 mol %)
O2 (1 atm), ROH, 50C, 30 min
n-C8H17O
n-C8H17
O
+
R = EtOH 16 : 84 selectivity, 22 %R = iPrOH 42 : 58 selectivity, 11 %R = tBuOH 84 : 16 selectivity, 7 %
n-C8H17
Ogura, T.; Kamimura, R.; Shiga, A.; Hosokawa, T. Bull. Chem. Soc. Jpn. 2005, 78, 1555.
Strategy:•PdCl2 complexes/styrene starting materials
• t-BuOH as solvent
PROPOSED CATALYTIC RELAY
PdCl2
Ar
Ar
PdCl Cl
t-BuOH
Art-BuO
PdCl
Ar
PdClt-BuO
trans hydroxy-palladation (external attack of water)
cis hydroxy-palladation (syn delivery of hydroxide)
or
Ar
PdH Cl
Ar
t-BuO
[M] H
Ar
O
Ar
O
H
[M]
H-Cl
[M] Cl H-Cl
t-BuO
?
[O]
Ar
HO
SHVO’S CATALYST
Shvo, Y.; Czarkie, D. J. Organomet. Chem. 1986, 315, C25.
Strategy:•Use Shvo’s catalyst but add alcohol as hydride source?
Casey, C. P.; Singer, S.; Powell, D. R.; Hayashi, R. K.; Kavana, M. J. Am. Chem. Soc. 2001, 123, 1090.
OPhPh
PhPh H
RuC
O CO
H
O Ph
Ph
Ph
PhRu
C
O
CO
Shvo's catalyst
OPhPh
PhPh H
RuC
O CO
H
O Ph
Ph
Ph
PhRu
C
O
CO
+O
PhPh
PhPh H
RuC
O CO
HO
H R
O Ph
Ph
Ph
PhRu
C
O
CO
H
HRR
O
OH OAc
Shvo catalyst (2 mol %)Novozym 435
4ClPhOAc (4 eq.)
PhMe, 70 C, 46 h80 %, > 99 % ee
Persson, B. A.; Larsson, A. L. E.; Le Ray, M.; Backvall, J.-E. J. Am. Chem. Soc. 1999, 121, 1645.
PROPOSED CATALYTIC RELAY: TRIPLE RELAY
PdCl2
Ar
Ar
PdCl Cl
t-BuOH
Art-BuO
PdCl
Ar
PdClt-BuO
trans hydroxy-palladation (external
attack of water)
cis hydroxy-palladation (syn delivery of
hydroxide)
Ar
PdH Cl
Ar
t-BuO
Ar
O
H-Cl
OPhPh
PhPh H
RuC
O CO
H
t-BuO
?
OPh
Ph
Ph
PhRu
C
O
CO
H
H H
O Ar
O
PhPh
PhPh
RuC
O CO
OH
MeMe
O
MeMe[O]
Ar
HO
PROPOSED CATALYTIC RELAY: TRIPLE RELAY
PdCl2
Ar
Ar
PdCl Cl
t-BuOH
Art-BuO
PdCl
Ar
PdClt-BuO
trans hydroxy-palladation (external
attack of water)
cis hydroxy-palladation (syn delivery of
hydroxide)
Ar
PdH Cl
Ar
t-BuO
Ar
OHCl + H2O O
PhPh
PhPh H
RuC
O CO
H
t-BuO
OPh
Ph
Ph
PhRu
C
O
CO
H
H H
O Ar
O
PhPh
PhPh
RuC
O CO
OH
MeMe
O
MeMe
t-BuOH
HCl becomes 3rd
catalyst !!!
[O]
PdCl2
Ar
HO
PRELIMINARY RESULTS
Controls:•No palladium catalyst 26 % of desired product (34 % conv.)
• No Shvo catalyst: only aldehyde product 42 %• No Shvo catalyst or water: 17 %
• No CuCl2: 48 % of desired product (32 % ethylbenzene)• No benzoquinone 58% conv, almost no by-products ???
• No iPrOH 57% aldehyde• No tBuOH 58% conv, 18 % desired product.
• No tBuOH but 28 eq. H2O 64 % desired product• no H2O, but 4A MS, 57 % ethyl benzene
Ot-Bu
Shvo's catalyst (10 mol %)PdCl2(MeCN)2 (10 mol %)
H2O (1.1 eq.)
CuCl2 (20 mol %)benzoquinone (80 mol %)iPrOD/tBuOD (1:2), 85 C
OD/H
69 %
DOD/H
D
+
D
31 %
Shvo's catalyst (10 mol %)PdCl2(MeCN)2 (10 mol %)
H2O (1.1 eq.)
CuCl2 (20 mol %)benzoquinone (80 mol %) /tBuOD (1:2), 85 C
OD/H
65 %
DOD/H
D
+
D
35 %
OD
MeMeD
D D
Shvo's catalyst (10 mol %)PdCl2(MeCN)2 (10 mol %)
H2O (1.1 eq.)
CuCl2 (20 mol %)benzoquinone (80 mol %)iPrOH/tBuOH (1:2), 85 C
OH
77 %
OH
1.3 % 0.7 %
OO
1.4 % 1.5 %
SCOPE
R
Shvo's catalyst (10 mol %)PdCl2(MeCN)2 (10 mol %)
H2O (1.1 eq.)
CuCl2 (20 mol %)benzoquinone (80 mol %)iPrOH/tBuOH (1:2), 85 C
ROH
OH
84 %
OH
42 %
OH
61 %
OH
60 %
OH
72 %
OH
75 %
OH
72 %
OH
63 %
OH
83 %
OH
74 %Cl FBr O2N
F3C
CF3
OHOH
56 % 12 %
>20 : 1 >20 : 1 >20 : 1 >20 : 1 >20 : 1
>20 : 1>20 : 1>20 : 1>20 : 1>20 : 1
1 : 1.4 1 : 2.1
SUMMARY.
Compared to the classic hydroboration/oxidation sequence, our approach is still far from perfect, with its relatively high catalyst loadings and use of stoichiometric BQ. However, we are strongly encouraged by the excellent selectivity with arylsubstituted olefins, initial promising results with aliphatic alkenes, and the facile recovery of BQ to reduce the overall expense. Despite being in its infancy, this methodology has demonstrated great potential and will stimulate ongoing research in the field of olefin hydration
EXTENSION TO HYDROAMINATION
NMePh1) PdCl2(PhCN)2 (10 mol %)
BQ (1 eq.), H2O, t-BuOH, 35 C
2) N-Me aniline (2.5 eq.) Ir catalyst (10 mol %)
5:2 formic acid:TEA azeotrope, 85 C66 %
N
MeO
OMe
Ir Cl
Bronner, S. M.; Grubbs, R. H. Chem. Sci. 2014, 5, 101.