A R T I C L E S
Selander et al.
functional group tolerance arising from the high reactivity of
the allyl metal species. On the other hand, high selectivity and
functional group tolerance can be achieved in transition-metal-
catalyzed procedures for generation of allyl boronates,22-30
which often involves application of diboronates as a source of
the boronate functionality. In this respect, palladium-,22-26
platinum-,27,28,31 nickel-,29 and copper-catalyzed30,32 boronation
of allenes, dienes, and substituted allylic substrates represent
the most efficient procedures.
Considering the relatively low stability of the functionalized
allyl boronates, their isolation and purification often becomes
a major issue (ii, above), which may encumber the synthetic
application of allyl boronates. Allyl boronic acids are more
reactive allylating reagents17,33 than allyl boronate esters;
however, these species rapidly decompose (probably oxidized)
under solvent-free conditions.20,23,34,35 An attractive solution for
the above purification issues is the development of one-pot
procedures, in which the transient allyl boronates are not isolated
butdirectlyreactedwiththecorrespondingallylacceptors.18,23,32,34,36-38
Development of these procedures requires highly selective
formation of allyl boronates and carefully designed reaction
conditions to avoid undesired side products in the multicom-
ponent processes. We18,34,36 and others32,37,38 have shown that
transition-metal-catalyzed generation of allyl boronates followed
by subsequent allylation of aldehydes can be performed in a
one-pot sequence. In a couple of recent communications,23,24,36
we have shown that allyl boronates can be efficiently prepared
from simple allylic substrates, such as allyl alcohols, employing
palladium pincer complex39-44 catalysis. This efficient boryla-
tion procedure can be integrated in a one-pot sequence36 for
stereo- and regioselective carbon-carbon bond coupling of allyl
alcohols and aldehydes. The selective coupling reaction proceeds
via generation of transient allyl boronic acids from diboronic
acid45 as boronate source. In this paper, we give a full account
of our results with extending the allyl-alcohol-based allylation
procedures to new one-pot transformations, new reagents, and
catalysts. These new results clearly indicate that complex, highly
Figure 1. General scheme of the studied one-pot reactions for synthesis
of homoallyl alcohols and R-amino acids via catalytic generation of allyl
boronates.
functionalized, regio- and stereodefined products can easily be
prepared from allyl alcohols via catalytic generation of allyl
boronates in a one-pot sequence. Furthermore, the cost efficiency
of the transformations has been improved by application of a
new boronate source and catalyst. The new aspects of the full
paper version can be summarized as follows: (a) Extension of
the synthetic scope of the reaction to the Petasis borono-Mannich
reaction is achieved.14,16,17,46,47 Using this procedure stereo- and
regiodefined R-amino acids48-55 can be prepared from inex-
pensive allyl alcohols in a multicomponent one-pot reaction.
(b) Allylation of ketones by in situ generated allyl boronic acids
in the presence of catalytic amounts of InI takes place.9 (c) By
appropriate choice of the reaction conditions and allyl alcohol
substrates, selective carbon-carbon bond formation involving
quaternary carbons can be achieved. (d) The reactions are made
suitable for one-pot stereoselective synthesis of 1,7-dienes,
which are useful precursors for Grubbs-cyclization.56,57(e) With
a slight change of the reaction conditions, the one-pot procedures
can be performed using commercially readily available bis-
(pinacolato)diboron in place of diboronic acid. (f) A new SCS
based pincer complex catalyst was introduced as a complement
for the very efficient and easily accessible selenium based SeCSe
complex. A new straightforward procedure for synthesis of this
latter complex is included in the Supporting Information.
(22) Ishiyama, T.; Ahiko, T.-A.; Miyaura, N. Tetrahedron Lett. 1996, 37, 6889.
(23) Sebelius, S.; Olsson, V. J.; Szabo´, K. J. J. Am. Chem. Soc. 2005, 127,
10478.
(24) Olsson, V. J.; Sebelius, S.; Selander, N.; Szabo´, K. J. J. Am. Chem. Soc.
2006, 128, 4588.
(25) Suginome, M.; Ohmura, T.; Miyake, Y.; Mitani, S.; Ito, Y.; Murakami,
M. J. Am. Chem. Soc. 2003, 125, 11174.
(26) Yang, F.-Y.; Cheng, C.-H. J. Am. Chem. Soc. 2001, 123, 761.
(27) Ishiyama, T.; Yamamoto, M.; Miyaura, N. Chem. Commun. 1996, 2073.
(28) Clegg, W.; Johann, T. R. F.; Marder, T. B.; Norman, N. C.; Orpen, A. G.;
Paekman, T. M.; Quayle, M. J.; Rice, C. R.; Scott, A. J. J. Chem. Soc.,
Dalton Trans. 1998, 1431.
(29) Suginome, M.; Matsuda, T.; Yoshimoto, T.; Ito, Y. Org. Lett. 1999, 1,
1567.
(30) Ito, H.; Kawakami, C.; Sawamura, M. J. Am. Chem. Soc. 2005, 127, 16034.
(31) Suginome, M.; Nakamura, H.; Matsuda, T.; Ito, Y. J. Am. Chem. Soc. 1998,
120, 4248.
(32) Carosi, L.; Hall, D. G. Angew. Chem., Int. Ed. 2007, 46, 5913.
(33) Brown, H. C.; Racherla, U. S.; Pellechia, P. J. J. Org. Chem. 1990, 55,
1868.
2. Results and Discussion
As mentioned above, the present studies (Figure 1) are mostly
directed to one-pot synthesis of functionalized homoallyl
alcohols (9) and R-amino acids (10) from inexpensive, easily
accessible allyl alcohols (1). The reactions proceed via pincer-
(34) Sebelius, S.; Szabo´, K. J. Eur. J. Org. Chem. 2005, 2539.
(35) Sebelius, S.; Olsson, V. J.; Wallner, O. A.; Szabo´, K. J. J. Am. Chem. Soc.
2006, 128, 8150.
(46) Petasis, N. A.; Zavialov, I. A. J. Am. Chem. Soc. 1997, 119, 445.
(47) Petasis, N. A.; Zavialov, I. A. J. Am. Chem. Soc. 1998, 120, 11798.
(48) Kazmaier, U.; Zumpe, F. L. Angew. Chem., Int. Ed. 1999, 38, 1468.
(49) Zumpe, F. L.; Kazmaier, U. Synlett. 1998, 1199.
(36) Selander, N.; Sebelius, S.; Estay, C.; Szabo´, K. J. Eur. J. Org. Chem. 2006,
4085.
(50) Kazmaier, U. Angew. Chem., Int. Ed. 1994, 33, 998.
(51) Kazmaier, U.; Krebs, A. Angew. Chem., Int. Ed. 1995, 34, 2012.
(52) Bakke, M.; Ochta, H.; Kazmaier, U.; Sugai, T. Synthesis 1999, 1671.
(53) Mock, M. L.; Michon, T.; Hest, J. C. M. v.; Tirrell, D. A. ChemBiochem.
2006, 7, 83.
(37) Goldberg, S. D.; Grubbs, R. H. Angew. Chem., Int. Ed. 2002, 41, 807.
(38) Kabalka, G. W.; Venkataiah, B.; Dong, G. J. Org. Chem. 2004, 69, 5807.
(39) Albrecht, M.; Koten, G. v. Angew. Chem., Int. Ed. 2001, 3750.
(40) Dupont, J.; Consorti, C. S.; Spencer, J. Chem. ReV. 2005, 105, 2527.
(41) Boom, M. E. v. d.; Milstein, D. Chem. ReV. 2003, 103, 1759.
(42) Singleton, J. T. Tetrahedron 2003, 59, 1837.
(43) Beletskaya, I. P.; Cheprakov, A. V. J. Organomet. Chem. 2004, 689, 4055.
(44) Szabo´, K. J. Synlett. 2006, 811.
(45) Baber, R. A.; Norman, N. C.; Orpen, A. G.; Rossi, J. New J. Chem. 2003,
27, 773.
(54) Ellis, T. K.; Ueki, H.; Yamada, T.; Ohfune, Y.; Soloshonok, V. A. J. Org.
Chem. 2006, 71, 8572.
(55) Soloshonok, V. A.; Cai, C.; Hruby, V. C.; Meervelt, L. V.; Yamazaki, T.
J. Org. Chem. 2000, 65, 6688.
(56) Trnka, T. M.; Grubbs, R. H. Acc. Chem. Res. 2001, 34, 18.
(57) Heo, J.-N.; Micalizio, G. C.; Roush, W. R. Org. Lett. 2003, 5, 1693.
9
13724 J. AM. CHEM. SOC. VOL. 129, NO. 44, 2007