Tandem deployment of indium-, ruthenium-, and lead-promoted reactions. Four-carbon intercalation between the carbonyl groups of open-chain and cyclic α-diketones

Article abstract of DOI:10.1021/ol000037o

(equation presented) An efficient strategy for the conversion of 1,2-diketones into saturated 1,6-diketones and Δ^2,3/Δ^3,4-unsaturated congeners thereof is reported.

Full text of DOI:10.1021/ol000037o

ORGANIC
LETTERS
2000
Vol. 2, No. 9
1263-1265
Tandem Deployment of Indium-,
Ruthenium-, and Lead-Promoted
Reactions. Four-Carbon Intercalation
between the Carbonyl Groups of
Open-Chain and Cyclic r-Diketones
Jose´ Me´ndez-Andino and Leo A. Paquette*
EVans Chemical Laboratories, The Ohio State UniVersity, Columbus, Ohio 43210
paquette.1@osu.edu
Received February 18, 2000
ABSTRACT
An efficient strategy for the conversion of 1,2-diketones into saturated 1,6-diketones and ∆2,3/∆3,4-unsaturated congeners thereof is reported.
Chain-extension1 and ring-enlargement reactions2,3 play a
major role in modern organic synthesis. Although a variety
of tactics for achieving such transformations has been
reported, little is known about the controlled insertion of
carbon chains of differing length between the carbonyl
groups of R-diketones. Consequently, we have targeted for
investigation a convenient means for achieving four-carbon
intercalation. Our results establish that a three-step sequence
consisting of diallylation, ring-closing metathesis, and oxida-
tive diol cleavage with Pb(IV) acetate (with or without prior
hydrogenation) lends itself conveniently to useful structural
modifications of this type.
3:2 (Scheme 1). Without separation, these diols were
converted to 3 by exposure to Grubbs catalyst5 in CH2Cl2
under argon. Direct addition of 1.1 equiv of lead tetraacetate6
resulted in cleavage of the diol to 4 (66% overall)7 with
effective removal of the highly colored olefin metathesis
catalyst impurities by filtration through a pad of silica gel.8
Prior catalytic hydrogenation of 3 to 59 made possible the
analogous conversion to 6.10
Our attempts to effect comparable structural homologation
of diketone 7a and keto aldehyde 7b again proceed ef-
ficiently, but with some notable outcomes (Scheme 2). In
(4) (a) Masuyama, Y.; Tsunoda, T.; Kusuru, Y. Chem. Lett. 1989, 1647.
(b) Gewald, K.; Kira, M.; Sakurai, H. Synthesis 1996, 111.
(5) Fu, G.; Grubbs, R. H. J. Am. Chem. Soc. 1992, 114, 5426.
(6) Mihailovic, M. Lj.; Cekovic, Z. Encyclopedia of Reagents for Organic
Synthesis; Paquette, L. A., Editor -in-Chief; Wiley: Chichester, 1995; Vol.
5, p 2949.
The protocol was initially investigated with biacetyl (1)
whose reaction with allyl bromide and indium powder in
THF-water (1:4) afforded 24 in a diastereomeric ratio of
(1) Ho, T.-L Polarity Control for Synthesis; John Wiley and Sons: New
York, 1991.
(2) Gutsche, C. D.; Redmore, D. Carbocyclic Ring Expansion Reactions;
Academic Press: New York, 1968.
(3) Hesse, M. Ring Enlargement in Organic Chemistry; VCH Publish-
ers: Weinheim, 1991.
(7) The reported trans isomer exhibits a very different 1H NMR
spectrum: Yasuda, H.; Okamoto, T.; Mashima, K.; Nakamura, A. J.
Organomet. Chem. 1989, 363, 61.
(8) Paquette. A.; Schloss, J. D.; Efremov, I.; Fabris, F.; Gallou, F.;
Mendez-Andino, J.; Yang. J. Org. Lett. 2000, 2, 1259.
(9) Hauptmann, S.; Dietrich, K. J. Prakt. Chem. 1963, 19, 174.
10.1021/ol000037o CCC: $19.00 © 2000 American Chemical Society
Published on Web 04/04/2000

Scheme 1
Scheme 2
both of these examples, the diastereomeric ratios of allylated
diols (7:1 and 10:1, respectively)4b,11 were significantly more
elevated than in the case of 2. An increased bias for formation
of the anti diols was deduced by analysis of the relevant
chemical shifts exhibited by 9a and 9b.12,13 This phenomenon
may be indicative of a significantly greater preference for
adoption of chelated transition states.14 Although 10a, 12a,15
and 12b16 were obtained with ease, 10b could not be
characterized because of its marked sensitivity to polymer-
ization.
A pair of cyclic substrates has been studied in detail. The
2-fold allylindation of 1,2-cyclohexanedione under the pre-
described aqueous conditions proceeded rapidly at the 0.08
M level to furnish 13 in 92% yield (Scheme 3). Exposure of
13 to the Grubbs catalyst in CH2Cl2 provided bicyclic diol
1417 as a 3:1 mixture of diastereomers. Sequential catalytic
hydrogenation afforded 1518 from which 1,6-cyclodecanedi-
one (16)19 was derived. Once again, the introduction of lead
tetraacetate immediately after completion of the ring-closing
metathesis was found to be optimal in providing 17 and 18
as a 3:2 mixture in 69% overall yield. In 17 where no double
bond migration occurs, the olefinic linkage must necessarily
be cis. When conjugation does materialize as in 18, the
favored double bond geometry is trans (J2,3 ) 11.9 Hz).
Implementation of the allylindation of 1920 was met with
exclusive monoaddition. The second 1,2-addition occurred
uneventfully when recourse was made to the allyl Grignard
reagent in anhydrous ether. These conditions gave rise in
83% yield to a single diasteriomer of 20 (Scheme 4).
Activation of the terminal vinyl groups in this diol with the
Grubbs catalyst elaborated 21 in essentially quantitative yield.
From this point, it proved an easy matter to generate pure
2221 or a mixture of 23 and 24, which could be readily
separated by chromatography.
(10) Barbot, F.; Aidene, M.; Miginiac, L. Synth. Commun. 1998, 28,
3279.
(11) Kobayashi, S.; Hachiya, I. J. Org. Chem. 1993, 58, 6958.
(12) The methyl protons of 9a (δ 1.05) experience significant shielding
as a consequence of their position relative to the phenyl ring.
(13) (a) Diol 11a is known: Fujiwara, T.; Tsuruta, Y.; Arizono, K.;
Takeda T. Synlett 1997, 962. (b) For 11b, see: Berti, G.; Bottari, F.;
Macchia, B.; Macchia, F. Tetrahedron 1965, 21, 3277. (c) Delgado, A.;
Granados, R.; Mauleon, D.; Soucheiron, I.; Feliz, M. Can. J. Chem. 1985,
63, 3186.
(14) Paquette, L. A.; Mitzel, T. M. J. Am. Chem. Soc. 1996, 118, 1931.
(15) Nishinaga, A.; Rindo, K.; Matsuura, T. Synthesis 1986, 1038.
(16) (a) Yamaguchi, M.; Takada, T.; Endo, T. J. Org. Chem. 1990, 55,
1490. (b) Kabalka, G. W.; Yu, S.; Li, N.-S. Can. J. Chem. 1998, 76, 800.
(17) The trans isomer of 14 has been reported: Hueckel, W. Chem. Ber.
1956, 89, 2098, 2102.
(18) (a) Dev, S. J. Ind. Chem. Soc. 1954, 1, 5. (b) Betzemeier, B.;
Lhermite, F.; Knochel, P. Synlett 1999, 489.
(19) House, H. O.; Lee, J. H. C.; Van Deveer, D.; Wassinger, J. E. J.
Org. Chem. 1983, 48, 5285.
(20) Kawada K.; Gross, R. S.; Watt, D. S. Synth. Commun. 1989, 19,
777.
(21) Leriverend, P.; Conia, J.-M. Bull. Soc. Chim. Fr. 1970, 1040.
1264
Org. Lett., Vol. 2, No. 9, 2000

Scheme 3
Scheme 4
It was at this point that the diminished reactivity of 19
toward the allylindium reagent was briefly probed. These
ancillary studies make clear that other R-diketones share this
reluctance to enter into 2-fold addition in an aqueous
environment. Included in this group are 1,2-cyclooctanedi-
one, 5-cyclooctene-1,2-dione, camphorquinone, and dimethyl
squarate. The exceptionally high enol character of 3-methyl-
1,2-cyclopentanedione deterred even simple monoaddition.
our intention to explore in greater detail various aspects of
these intercalation processes.
Acknowledgment. A generous gift of the Grubbs catalyst
from Dr. Craig Blankenship (Boulder Scientific Co.) is
gratefully acknowledged. J.M.-A. thanks the Procter and
Gamble company for fellowship support.
The ease of obtaining systems such as 2, 8, 13, and 20,
the very mild conditions required for their cyclization via
ring-closing metathesis, and the capability to access 1,6-
diketones by direct treatment of the metathesis reaction
mixtures with Pb(OAc)4 render this protocol of demonstrable
synthetic merit. Considerable potential lies beyond the realm
of allylation, where longer chains having terminal double
bonds would give rise to diketone products having carbonyl
groups separated by 6-20 carbons or more on demand. It is
Supporting Information Available: Representative ex-
amples of experimental procedures. This material is available
free of charge via the Internet at http://pubs.acs.org.
OL000037O
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