Organometallics
Article
(3) Baldwin, J. E. J. Chem. Soc., Chem. Commun. 1976, 734.
point to the lanthanum-catalyzed process and our previous
observations in group 2-catalyzed hydroamination cataly-
sis,13,18,19 however, substantial positive ΔS⧧ values for all
three amides were deduced. Calculation of the corresponding
free energies of activation, ΔG⧧, produced commensurate
values for all three alkaline earth-based catalytic systems (Table
5). We interpret this latter observation to indicate that the
catalytic hydroalkoxylation/cyclization of compound 11 is
subject to a high degree of overall entropic control and suggest
that these observations in conjunction with the inverse
dependence of the cyclization reaction rate upon [substrate]
(Figures 7 and 8) are suggestive of a catalyst resting state in
which additional substrates are strongly bound and congest the
oxophilic alkaline earth centers.26 Consequent formation of the
CC insertion transition state will, thus, necessarily require
either dissociation of substrate molecules from the metal
coordination sphere or possibly disruption of a relatively
ordered and/or metal-templated hydrogen-bonded network. In
mitigation of this hypothesis, we note that positive ΔS⧧ values
of similar magnitudes to those displayed in Table 5 are
observed in enzymatic catalysis and have been interpreted in
terms of hydration of the reacting species, which release water
molecules in the chemical transition state.27
(4) Bruce, M. I.; Swincer, A. G.; Stone, F. G. A.; Robert, W. Advances
in Organometallic Chemistry; Academic Press: New York, 1983; Vol.
22.
(5) (a) McDonald, F. E.; Connolly, C. B.; Gleason, M. M.; Towne, T.
B.; Treiber, K. D. J. Org. Chem. 1993, 58, 6952. (b) McDonald, F. E.;
Schultz, C. C. J. Am. Chem. Soc. 1994, 116, 9363. (c) McDonald, F. E.
Chem.Eur. J. 1999, 5, 3103. , and references therein. (d) McDonald,
F. E.; Reddy, K. S. J. Organomet. Chem. 2001, 617, 444.
(6) Trost, B. M.; Rhee, Y. H. J. Am. Chem. Soc. 1999, 121, 11680.
́ ̀
(7) Compain, P.; Gore, J.; Vatele, J.-M. Tetrahedron 1996, 52, 10405.
(8) (a) Nakamura, I.; Yamamoto, Y. Chem. Rev. 2004, 104, 2127. ,
and references therein. (b) Gabriele, B.; Salerno, G.; Fazio, A.; Pittelli,
R. Tetrahedron 2003, 59, 6251. (c) Kadota, I.; Lutete, L. M.; Shibuya,
A.; Yamamoto, Y. Tetrahedron Lett. 2001, 42, 6207. (d) Cacchi, S. J.
Organomet. Chem. 1999, 576, 42. (e) Utimoto, K. Pure Appl. Chem.
1983, 55, 1845. (f) Wakabayashi, Y.; Fukuda, Y.; Shiragami, H.;
Utimoto, K.; Nozaki, H. Tetrahedron 1985, 41, 3655.
(9) Villemin, D.; Goussu, D. Heterocycles 1989, 29, 1255.
(10) Dalla, V.; Pale, P. New J. Chem. 1999, 23, 803.
(11) Harkat, H.; Weibel, J.-M.; Pale, P. Tetrahedron Lett. 2007, 48,
1439.
(12) Genin, E.; Antoniotti, S; Michelet, V.; Genet, J. P. Angew. Chem.,
Int. Ed. 2005, 44, 4949.
(13) (a) Yu, X.; Seo, S.; Marks, T. J. J. Am. Chem. Soc. 2007, 129,
7244. (b) Seo, S.; Yu, X.; Marks, T. J. J. Am. Chem. Soc. 2009, 131, 263.
(c) Weiss, C. J.; Marks, T. J. Dalton Trans. 2010, 39, 6576.
(14) For an assessment by density functional theory, see: Motta, A.;
̀
Fragala, I. L.; Marks, T. J. Organometallics 2010, 29, 2004.
(15) For examples, see: Hong, S.; Marks, T. J. Acc. Chem. Res. 2004,
37, 673.
(16) Barrett, A. G. M.; Crimmin, M. R.; Hill, M. S.; Procopiou, P. A.
Proc. R. Soc., A 2010, 466, 927.
(17) (a) Hitchcock, P. B.; Lappert, M. F.; Lawless, G. A.; Royo, B. J.
Am. Chem. Soc. 1990, 30, 96. (b) Westerhausen, M. Inorg. Chem. 1991,
30, 96.
(18) (a) Crimmin, M. R.; Arrowsmith, M.; Barrett, A. G. M.; Casely,
I. J.; Hill, M. S.; Procopiou, P. A. J. Am. Chem. Soc. 2009, 131, 9670.
(b) Arrowsmith, M.; Crimmin, M. R.; Barrett, A. G. M.; Hill, M. S.;
CONCLUSION
■
Intramolecular hydroalkoxylation/cyclization of alkynyl and
allenyl alcohols may be mediated by readily available heavier
alkaline earth bis(trimethylsilyl)amide derivatives. Although the
basicity of the [M{N(SiMe3)2}2]2 precatalysts opens up
isomerization pathways for less activated alkynyl alcohols, all
three metal complexes show good catalytic activity for primary
terminal and internal alkynyl alcohols. The reactivity of these
catalysts is strongly dependent on substrate substitution and is
most likely due to a subtle interplay of the ability of the metal
cations to polarize the triple bond of the substrate and the ease
with which insertion of the C−C triple bond into the M−O
bond takes place.
Kociok-Kohn, G.; Procopiou, P. A. Organometallics 2011, 30, 1493.
̈
(19) (a) Barrett, A. G. M.; Brinkmann, C.; Crimmin, M. R.; Hill, M.
S.; Hunt, P.; Procopiou, P. A. J. Am. Chem. Soc. 2009, 131, 12906.
(b) Brinkmann, C.; Barrett, A. G. M.; Hill, M. S.; Procopiou, P. A. J.
Am. Chem. Soc. 2012, 134, 2193.
ASSOCIATED CONTENT
* Supporting Information
Experimental and kinetic details. This material is available free
■
S
(20) (a) Bo, L.; Roisnel, T.; Carpentier, J. F.; Sarazin, Y. Angew.
Chem., Int. Ed. 2012, 51, 4943. (b) Bo, L.; Carpentier, J.-F.; Sarazin, Y.
Chem.−Eur. J. 2012, 18, in press; DOI: 10.1002/chem.201201489.
(21) Jung, M. E.; Piizzi, G. Chem. Rev. 2005, 105, 1735.
(22) Ribeiro da Silva, M. A. V.; Pilcher, G.; Irving, R. J. J. Chem.
Therm. 1988, 20, 95.
(23) Barrett, A. G. M.; Crimmin, M. R.; Hill, M. S.; Hitchcock, P. B.;
Lomas, S. L.; Procopiou, P. A.; Suntharalingam, K. Chem. Commun.
2009, 2299.
(24) For examples of allene hydroalkoxylation, see: (a) Zhang, Z.;
Widenhoefer, R. A. Angew. Chem., Int. Ed. 2007, 46, 283. (b) Ma, S.
Chem. Rev. 2005, 105, 2829. (c) Bates, R. W.; Satcharoen, V. Chem.
Soc. Rev. 2002, 31, 12. (d) Mukai, C.; Yamashita, H.; Hanaoka, M. Org.
AUTHOR INFORMATION
Notes
The authors declare no competing financial interest.
■
ACKNOWLEDGMENTS
We thank EPSRC UK for funding (EP/I014519/1) and
GlaxoSmithKline for the generous endowment (to A.G.M.B.).
■
Lett. 2001, 3, 3385. (e) Brown, T. J.; Weber, D.; Gagne,
Widenhoefer, R. A. J. Am. Chem. Soc. 2012, 134, 9134. (f) For a recent
́
M. R.;
REFERENCES
■
(1) (a) Elliot, M. C. J. Chem. Soc., Perkin Trans. 1 2000, 1291.
(b) Elliot, M. C.; Williams, E. J. Chem. Soc., Perkin Trans. 1 2001, 2303.
(c) Boivin, T. L. B. Tetrahedron 1987, 43, 3309. (d) Kotsubi, H. Synlett
1992, 97.
(2) (a) Mitchinson, A.; Nadin, A. J. Chem. Soc., Perkin Trans. 1 2000,
2862. (b) Perron, F.; Albizati, K. F. Chem. Rev. 1989, 89, 1617.
(c) Mead, K. T.; Brewer, B. N. Curr. Org. Chem. 2003, 7, 227.
(d) Brimble, M. A.; Furkert, D. P. Curr. Org. Chem. 2003, 7, 1461.
(e) Schwartz, B. D.; Hayes, P. Y.; Kitching, W.; DeVoss, J. J. J. Org.
Chem. 2005, 70, 3054. (f) Pietruszka, J. Angew. Chem., Int. Ed. 1998,
37, 2629. (g) Francke, W.; Kitching, W. Curr. Org. Chem. 2001, 5, 233.
review, see: Munoz, M. P. Org. Biomol. Chem. 2012, 10, 3584.
̃
(25) Walsh, P. J.; Baranger, A. M.; Bergman, R. G. J. Am. Chem. Soc.
1992, 114, 1708.
(26) Anslyn, E. V.; Dougherty, D. A. Modern Physical Organic
Chemistry; University Science Books: Sausalito, CA, 2006.
́
(27) Szeltner, Z.; Polgar, L. J. Biol. Chem. 1996, 271, 32180.
(28) Li, Y.; Fu, P.-F.; Marks, T. J. Organometallics 1994, 13, 439.
(29) Ryu, J. S.; Li, G. Y.; Marks, T. J. J. Am. Chem. Soc. 2003, 125,
12584.
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dx.doi.org/10.1021/om3008663 | Organometallics 2012, 31, 7287−7297