The discovery of novel reactivity in the development of C-C bond-forming reactions: In situ generation of zinc acetylides with Zn11/R3N

Accounts of Chemical Research

Volumn 33, Issue 6, 2000, Pages 373-381

  Frantz, Doug E ^a,b   Fässler, Roger ^a   Tomooka, Craig S ^a   Carreira, Erick M ^a  

^a ETH ZURICH   (Switzerland)

^b MERCK RESEARCH LABORATORIES   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

ACETYLENE DERIVATIVE; ALDEHYDE DERIVATIVE; ALKENE; ALKYNE; AMINE; ESTER; IMINE; KETONE; METAL DERIVATIVE; NITRONE DERIVATIVE; ORGANOMETALLIC COMPOUND; SILANE DERIVATIVE; UNCLASSIFIED DRUG; ZINC; ZINC ACETYLIDE; ZINC DERIVATIVE;

ARTICLE; CATALYSIS; CHEMICAL BOND; CHEMICAL REACTION; CHEMICAL STRUCTURE; CHEMISTRY; CONFORMATION; REACTION ANALYSIS; STEREOCHEMISTRY; STEREOISOMERISM; SYNTHESIS;

ALKENES; ALKYNES; AMINES; CATALYSIS; ESTERS; IMINES; KETONES; MOLECULAR CONFORMATION; ORGANOMETALLIC COMPOUNDS; SILANES; STEREOISOMERISM; ZINC;

EID: 0038252959     PISSN: 00014842     EISSN: None     Source Type: Journal    
DOI: 10.1021/ar990078o     Document Type: Article

References (109)

1. Corey, E. J.; Cheng, X.-M. The Logic of Chemical Synthesis; Wiley: New York, 1989.
2. Carreira, E. M. In Comprehensive Asymmetric Catalysis; Jacobsen, E. N., Pfaltz, A., Yamamoto, H., Eds.; Springer: Berlin, 1999; Chapter 29, p 997.
3. Danishefsky, S. J. Cycloaddition and Cyclocondensation Reactions of Highly Functionalized Dienes: Application to Organic Synthesis. Chemtracts: Org. Chem. 1989, 273 and references therein.
4. Vanagisawa, A. In Comprehensive Asymmetric Catalysis; Jacobsen, E. N., Pfaltz, A., Yamamoto, H., Eds.; Springer: Berlin, 1999; Chapter 27, p 965.
5. Soai, K.; Shibata, T. In Comprehensive Asymmetric Catalysis; Jacobsen, E. N., Pfaltz, A., Yamamoto, H., Eds.; Springer: Berlin, 1999; Chapter 26, p 911.
6. For key references to addition reactions employing stannyl, silylated, and boryl reagents, see: (a) Yamamoto, Y.; Nishii, S.; Maruyama, K. The Titanium Tetrachloride-Mediated Alkynylation and Allylation of a Steroidal Aldehyde via Stannylacetylenes and Allylstannanes with High Cram Selectivity. J. Chem. Soc., Chem. Commun. 1986, 102.
7. (b) Corey, E. J.; Cimprich, K. Highly Enantioselective Alkynylation of Aldehydes Promoted by Chiral Oxazaborolidines. J. Am. Chem. Soc. 1994, 116, 3151.
8. (c) Ahn, J. H.; Joung, M. J.; Yoon, N. M. Sodium Diethyldialkynylaluminate, a New Chemoselective Alkynylating Agent. J. Org. Chem. 1995, 60, 6173.
9. (d) Evans, D. A.; Halstead, D. P.; Allison, B. D. Chelation-controlled Stannylacetylene Additions to β-alkoxy Aldehydes Promoted by Alkylaluminum Halide Lewis Acids. Tetrahedron Lett. 1999, 40, 4461.
10. For general references, see: (a) Santelli, M.; Pons, J.-M. Lewis Acids and Selectivity in Organic Synthesis; CRC: Boca Raton, FL, 1996; Chapters 3 and 5.
11. (b) Marshall, J. A. Chiral Allylic and Allenic Stannanes as Reagents for Asymmetric Synthesis. Chem. Rev. 1996, 96, 31.
12. (c) Yamamoto, Y.; Asao, N. Selective Reactions Using Allylic Metals. Chem. Rev. 1993, 93, 22; 107.
13. Trost, B. M. The Atom Economy - A Search for Synthetic Efficiency. Science 1991, 254, 1471.
14. (a) Carreira, E. M.; Singer, R. A.; Lee, W. S. Catalytic, Enantioselective Aldol Additions with Methyl and Ethyl-Acetate O-Silyl Enolates - A Chiral Tridentate Chelate as a Ligand for Titanium-(IV). J. Am. Chem. Soc. 1994, 116, 8837.
15. (b) For an application, see: Kim, Y.; Singer, R. A.; Carreira, E. M. Total Synthesis of Macrolactin A with Versatile Catalytic, Enantioselective Dienolate Aldol Addition Reactions. Angew. Chem., Int. Ed. 1998, 37, 1261.
16. Carreira, E. M.; Singer, R. A. Advances in Catalytic, Enantioselective Aldol Addition Reactions with Novel Ti(IV) Complexes. Drug Disovery Today 1996, 1, 145.
17. (a) Mukaiyama, T.; Banno, K.; Narasaka, K. New Cross Aldol Reactions. Reactions of Silyl Enol Ethers with Carbonyl Compounds Activated by Titanium Tetrachloride. J. Am. Chem. Soc. 1974, 96, 7503.
18. (b) Mukaiyama, T. Titanium Tetrachloride in Organic Synthesis. Angew. Chem., Int. Ed. Engl. 1977, 16, 817.
19. For recent mechanistic discussions, see ref 2 along with the following: (a) Carreira, E. M.; Singer, R. A. Metal Versus Silyl Triflate Catalysis in the Mukaiyama Aldol Addition-Reaction. Tetrahedron Lett. 1994, 35, 4323.
20. (b) Hollis, T. K.; Bosnich, B. Homogeneous Catalysis-Mechanisms of the Catalytic Mukaiyama Aldol And Sakurai Allylation Reactions. J. Am. Chem. Soc. 1995, 117, 4570.
21. For exceptions, see: (a) Gong, L.; Streitwieser, A. Organolanthanide Catalysis of a Mukayama Addition Reaction. J. Org. Chem. 1990, 55, 6235.
22. (b) Chan, T. H.; Aida, T.; Lau, P. W. K.; Gorys, V.; Harpp, D. N. Stereoselection in the Condensation between Ethyl Propionate and Aldehydes. Tetrahedron Lett. 1979, 4029.
23. (c) Helmchen, G.; Leikauf, U.; Taufer-Knopfel, I. Enantioselective and Anti-Diastereoselective Aldol Additions of Acetates and Propionates via O-Silyl Ketene Acetals. Angew. Chem., Int. Ed. Engl. 1985, 24, 874.
24. (d) Trost, B. M.; Urabe, H. On 1,4-Diastereoselectivity in the Aldol Condensation of Methyl Ketones. J. Org. Chem. 1990, 55, 3982.
25. (e) Aben, R. W.; Scheeren, J. W. Synthesis of β-Hydroxy Esters from Ketene Acetals and Aldehydes or Ketones. An Acidic Alternative for the Reformatsky Reaction and Crossed Aldol Condensation. Synthesis 1978, 400.
26. (f) Sugimura, H.; Osumi, K. A. Formation of Optically-Active Oxetanes from Sugars by Boron-Trifluoride Catalyzed [2+2]-Cycloaddition Reaction. Tetrahedron Lett. 1989, 30, 1571.
27. (g) Bach, T. Stereoselective Photocycloaddition of Silyl Enol Ethers to Aldehydes-Configurational Control of 3 Stereogenic Centers in Oxetanes, Tetrahedron Lett. 1994, 35, 5845.
28. (h) Abe, M.; Ikeda, M.; Shirodai, Y.; Nojima, M. Regio- and Stereoselective Formation of 2-Siloxy-2-alkoxyoxetanes in the Photoreaction of Cyclic Ketene Silyl Acetals with 2-Naphthaldehyde and their Transformation to Aldol-Type Adducts. Tetrahedron Lett. 1996, 37, 5901.
29. (i) Mikami, K.; Matsukawa, S. Asymmetric Catalytic Aldol-Type Reaction with Ketene Silyl Acetals - Possible Intervention of the Silatropic Ene Pathway. J. Am. Chem. Soc. 1994, 116, 4077.
30. (j) Denmark, S. E.; Wong, K.-T.; Stavenger, R. A. The Chemistry of Trichlorosilyl Enolates. 2. Highly-Selective asymmetric Aldol Additions of Ketone Enolates. J. Am. Chem. Soc. 1997, 119, 2333.
31. (k) Denmark, S. E.; Griedel, B. D.; Coe, D. M.; Schnute, M. E. Chemistry of Enoxysilacyclobutanes - Highly Selective Uncatalyzed Aldol Additions. J. Am. Chem. Soc. 1994, 116, 7026.
32. (I) Myers, A. G.; Widdowson, K. L. A Silicon-Directed Aldol Condensation. Synthesis of Enantiomerically Pure Anti Aldols. J. Am. Chem. Soc. 1990, 112, 9672.
33. (m) Myers, A. G.; Widdowson, S. E. Silicon-Directed Aldol Condensation - Evidence for a Pseudorotational Mechanism. J. Am. Chem. Soc. 1992, 114, 2765.
34. (a) Heathcock, C. H.; Hug, K. T.; Flippin, L. A. Acyclic Stereoselection. 27. Simple Diastereoselection in the Lewis Acid Mediated Reactions of Enolsilanes with Aldehydes. Tetrahedron Lett. 1984, 25, 5973.
35. (b) Heathcock, C. H.; Davidsen, S. K.; Hug, K. T.; Flippin, L. A. Acyclic Stereoselection. 36. Simple Diastereoselection in the Lewis Acid Mediated Reactions of Enol Silanes with Aldehydes. J. Org. Chem. 1986, 51, 3027.
36. Carreira, E. M.; Lee, W. S.; Singer, R. A. Catalytic, Enantioselective Acetone Aldol Additions with 2-Methoxypropene. J. Am. Chem. Soc. 1995, 117, 3649,
37. For a leading discussion, see: Catalytic Asymmetric Synthesis; Ojima, I., Ed.; VCH: New York, 1993.
38. For a recent discussion of a novel mechanistic model involving aldehyde binding and activation in Lewis acid mediated additions, see: Corey, E. J.; Barnes-Seeman, D.; Lee, T. W. The Formyl C - H - O Hydrogen Bond as a Critical Factor in Enantioselective Reactions of Aldehydes. 4. Aldol, Ethylation, Hydrocyanation and Diels-Alder Reactions Catalyzed by Chiral B, Ti and Al Lewis Acids. Tetrahedron Lett. 1997, 38, 4351 and references therein.
39. (a) For a report in which the involvement of a Pd-enolate is suggested, see: Sodeoka, M.; Ohrai, K.; Shibasaki, M. Catalytic Asymmetric Aldol Reaction via Chiral Pd(II) Enolate in Wet DMF. J. Org. Chem. 1995, 60, 2648 and references therein,
40. (b) For a report in which the involvement of a Ln-acetone enolate is suggested, see: Shibasaki, M.; Sasai, H.; Arai, T. Asymmetric Catalysis with Heterobimetallic Compounds. Angew. Chem., Int. Ed. Engl. 1997, 36, 1237.
41. For related processes wherein putative chiral metal enolates are generated and undergo conjugate additions, isocyanoacetic ester aldol additions, nitroaldols, and enolate amination reactions, see: (a) Sasai, H.; Arai, T.; Satow, Y.; Houk, K. N.; Shibasaki, M. The First Heterobimetallic Multifunctional Asymmetric Catalyst. J. Am. Chem. Soc. 1995, 117, 6194.
42. (b) Ito, Y.; Sawamura, M.; Hayashi, T. Catalytic Asymmetric Aldol Reaction - Reaction of Aldehydes with Isocyanoacetate Catalyzed by a Chiral Ferrocenylphosphine-Gold(I) Complex. J. Am. Chem. Soc. 1986, 108, 6405.
43. (c) Sasi, H.; Suzuki, T.; Arai, S.; Arai, T.; Shibasaki, M. Basic Character of Rare-Earth-Metal Alkoxides - Utilization in Catalytic C - C Bond-Forming Reactions and Catalytic Asymmetric Nitroaldol Reactions. J. Am. Chem. Soc. 1992, 114, 4418.
44. (d) Evans, D. A.; Nelson, S. G. Chiral Magnesium Bis(Sulfonamide) Complexes as Catalysts for the Merged Enolization and Enantioselective Amination of N-Acyloxazolidinones. A Catalytic Approach to the Synthesis of Arylglycines. J. Am. Chem. Soc. 1997, 119, 6452.
45. (a) Yoshikawa, N.; Yamada, Y. M. A.; Das, J.; Sasai, H.; Shibasaki, M. Direct Catalytic Asymmetric Aldol Reaction. J. Am. Chem. Soc. 1999, 121, 4168.
46. (b) Yamada, Y. M. A.; Yoshikawa, N.; Sasai, H.; Shibasaki, M. Direct Catalytic Asymmetric Aldol Reactions of Aldehydes with Unmodified Ketones. Angew. Chem., Int. Ed. Engl. 1997, 36, 1871.
47. For example, see: Sodeoka, M.; Ohrai, K.; Shibasaki, M.; Catalytic Asymmetric Aldol Reaction via Chiral Pd(II) Enolate in Wet DMF. J. Org. Chem. 1995, 60, 2648.
48. Krüger, J.; Carreira, E. M. Apparent catalytic generation of chiral metal enolates: Enantioselective Dienolate Additions to Aldehydes Mediated by Tol-BINAP-Cu(II) Fluoride Complexes. J. Am. Chem. Soc. 1998, 120, 837.
49. Pagenkopf, B. L.; Krüger, J.; Stojanovic, A.; Carreira, E. M. Mechanistic Insights into Cu-Catalyzed Asymmetric Aldol Reactions: Chemical and Spectroscopic Evidence for a Metalloenolate Intermediate. Angew. Chem., Int. Ed. 1998, 37, 3124.
50. (S)-Tol-BINAP is the accepted abbreviation for (S)-(-)-2,2′-bis(di-p-tolylphosphino)-1,1′-binaphthyl, a commercially available diphosphine derivative.
51. Krüger, J.; Carreira, E. M. Convergent Synthesis of the Amphotericin Polyol Subunit Employing Asymmetric Dienolate Addition Reactions. Tetrahedron Lett. 1998, 39, 7013.
52. (a) Mikami, K.; Terada, M.; Nakai, T. Catalytic Asymmetric Glyoxylate Ene Reaction - A Practical Access to a-Hydroxy Esters in High Enantiomeric Purities. J. Am. Chem. 1990, 112, 3949.
53. (b) Mikami, K.; Narisawa, S.; Shimizu, M.; Terada, M. Asymmetric Desymmetrization by Enantioselective Catalysis of Carbonyl-Ene Reaction - Remote Internal Asymmetric Induction. J. Am. Chem. Soc. 1992, 114, 6566.
54. (c) Mikami, K.; Matsukawa, S. Enantioselective and Diastereoselective Catalysis of the Mukaiyama Aldol Reaction - Ene Mechanism in Titanium-Catalyzed Aldol Reactions of Silyl Enol Ethers. J. Am. Chem. Soc. 1993, 115, 7039.
55. Evans, D. A.; Burgey, C. S.; Paras, N. A.; Vojkowsky, T.; Tregay, S. T. C-2-Symmetric Copper(II) Complexes as Chiral Lewis Acids. Enantioselective Catalysis of the Glyoxylate-Ene Reaction. J. Am. Chem. Soc. 1998, 120, 5824.
56. Brandsma, L. Preparative Acetylene Chemistry, 2nd ed., Elsevier: Amsterdam, 1988.
57. (a) Castro, C. E.; Stephens, R. D. Substitutions By Ligands of Low Valent Transition Metals. A Preparation of Tolanes and Heterocycles from Aryl Iodides and Cuprous Acetylides. J. Org. Chem. 1963, 28, 2163.
58. (b) Simandi, L. I. In The Chemistry of Functional Groups; Patai, S., Rappoport, Z., Eds.; Wiley: New York, 1983; Supplement C, Part 1, pp 529-534.
59. (c) Chodkiewicz, W. Contribution à la Synthèse des Composés Acétylèniques. Ann. Chim. (Paris) 1957, 2, 819.
60. (d) Sevin, A.; Chodkiewicz, W.; Cadiot, P. Condensations des Halogènures Propargyliques et Allyliques Avec les Alkynes Vrais en Présence de Sel Cuivreux. Bull. Soc. Chim. Fr. 1974, 913.
61. (e) Sonogashira, K.; Tohda, Y.; Hagihara, N. A Convenient Synthesis Of Acetylenes: Catalytic Substitutions of Acetylenic Hydrogen with Bromoalkenes, Iodoarenes, and Bromopyridines. Tetrahedron Lett. 1975, 4467.
62. Modern Acetylene Chemistry, Stang, P. J., Diederich, F., Eds.; VCH: Weinheim, 1995.
63. Wakefield, B. J. Organolithium Methods; Academic: London, 1988; Chapter 3, p 32.
64. Wakefield, B. J. Organomagnesium Methods In Organic Synthesis; Academic: London, 1995; Chapter 3, p 46.
65. For a leading reference to enantioselective additions of stoichiometric zinc acetylides to aldehydes and ketones utilizing chiral amino alcohol-based ligands, see: Tan, L. S.; Cheng, C. Y.; Tillyer, R. D.; Grabowski, E. J. J.; Reider, P. J. A Novel, Highly Enantioselective Ketone Alkynylation Reaction Mediated by Chiral Zinc Aminoalkoxides. Angew. Chem., Int. Ed. 1999, 38, 711.
66. tBu in DMSO, see: Babler, J. H.; Liptak, V. P.; Phan, N. Alkoxide-Catalyzed Addition of Terminal Alkynes to Ketones. J. Org. Chem. 1996, 61, 416.
67. (b) During the preparation of this manuscript, an important, novel process was reported for the addition of terminal acetylenes to aliphatic aldehydes and ketones utilizing 10 mol % CsOH in DMSO: Tzalis, D.; Knochel, P. Cesium hydroxide: A Superior Base for the Catalytic Alkynylation of Aldehydes and Ketones and Catalytic Alkenylation of Nitriles. Angew. Chem., Int. Ed. 1999, 38, 1463.
68. Cotton, F. A.; Wilkinson, G.; Murillo, C. A.; Bochmann, M. Advanced Inorganic Chemistry, 6th ed.; Wiley: New York, 1999; Chapter 16, pp 681-683.
69. 2-Promoted Addition of 1-Alkynes to Aldehydes. J. Org. Chem. 1991, 56, 4091.
70. Similar large downfield shifts for the acetylenic carbons of alkynyl alkylzincs has been reported: Koning, A. J.; Van Rijn, P. E.; Boersma, J.; Van Der Kerk, G. J. M. Synthesis and Characterization of some ω-Dimethylamino-1-Akynylizing Compounds. J. Organomet. Chem. 1979, 174, 129.
71. Yoshida, Z.; Ishibe, N.; Ozoe, H. Hydrogen Bonding of Phenol with Acetylene and Allenes. J. Am. Chem. Soc. 1972, 94, 4948.
72. Stoichiometric ketone reductions: (a) Midland, M. M.; Tramontano, A.; Zderic, S. A. Preparation of Optically Active Benzyl-α-d Alcohol via Reduction by B-3α-Pinanyl-9-borabicyclo[3.3.1.]-nonane. A New Highly Effective Chiral Reducing Agent. J. Am. Chem. Soc. 1977, 99, 5211.
73. (b) Yamaguchi, S.; Mosher, H. S.; Pohland, A. A Reversal in Stereoselectivity Depending upon the Age of a Chiral Lithium Alkoxyaluminohydride Reducing Agent. J. Am. Chem. Soc. 1972, 94, 9254.
74. (c) Mishizawa, M.; Yamada, M.; Noyori, R. Highly Enantioselective Reduction of Alkynyl Ketones by a Binaphthol-Modified Aluminum Hydride Reagent. Asymmetric Synthesis of Some Insect Pheromones. Tetrahedron Lett. 1981, 22, 247.
75. (d) Brown, H. C.; Ramachandran, P. V. Asymmetric Reduction with Chiral Organoboranes Based on α-Pinene. Acc. Chem. Res. 1992, 25, 16.
76. (e) Bach, J.; Berenguer, R.; Garcia, J.; Loscertales, T.; Vilarrasa, J. Highly Enantioenriched Propargylic Alcohols by Oxazaborolidine-Mediated Reduction of Acetylenic Ketones. J. Org. Chem. 1996, 61, 9021.
77. Catalytic ketone reductions: (a) Helal, C. J.; Magriotis, P. A.; Corey, E. J. Direct Catalytic Enantioselective Reduction of Achiral α,β-Ynones. Strong Remote Steric Effects Across the C-C Triple Bond. J. Am. Chem. Soc. 1996, 118, 10938.
78. (b) Matsumura, K.; Hashiguchi, S.; Ikariya, T.; Noyori, R. Asymmetric Transfer Hydrogenation of α,β-Acetylenic Ketones. J. Am. Chem. Soc. 1997, 119, 8738.
79. (c) Parker, K. A.; Ledeboer, M. W. Asymmetric Reduction. A Convenient Method for the Reduction of Alkynyl Ketones. J. Org. Chem. 1996, 61, 3214.
80. Corey, E. J.; Cimprich, K. A. Highly Enantioselective Alkynylation of Aldehydes Promoted by Chiral Oxazaborolidines. J. Am. Chem. Soc. 1994, 116, 3151.
81. For the asymmetric addition of lithium and magnesium acetylides to trifluoromethyl aryl ketones, see: (a) Tan, L.; Chen, C. -Y.; Tillyer, R. D.; Grabowski, E. J. J.; Beider, P. A Novel, Highly Enantioselective Ketone Alkynylation Reaction Mediated by Chiral Zinc Aminoalkoxides. Angew. Chem., Int. Ed. 1999, 38, 711.
82. (b) For a recent report on the addition of aromatic aldehydes with alkynylzinc reagents generated in situ from terminal acetylenes and dimethylzinc, see; Li, Z.; Upadhyay, V.; DeCamp, A. E.; DiMichele, L.; Reider, P. J. Enantioselective Alkynylation of Aromatic Aldehydes Catalized by Readily Available Chiral Amino Alcohol-Based Ligands. Synthesis 1999, 1453.
83. (c) For a recent study of chelation controlled stannylacetylene additions to aldehydes see: Evans, D. A.; Halstead, D. P.; Allison, B. D. Chelation-Controlled Stannylacetylene Additions to β-Alkoxy Aldehydes Promoted by Alkylaluminum Halide Lewis Acids. Tetrahedron Lett. 1999, 40, 4461.
84. For the enantioselective addition of zinc acetylides (generated from the corresponding lithium acetylides) to aldehydes, see: Niwa, S.; Soai, K. Catalytic Asymmetric-Synthesis of Optically-Active Alkynyl Alcohols by Enantioselective Alkynylation of Aldehydes and by Enantioselective Alkylation of Alkynyl Aldehydes. J. Chem Soc., Perkin Trans. 1 1990, 937. Tombo, G. M. R.; Didier, E.; Loubinoux, B. Amino Alcohol Mediated Enantioselective Addition of 2-Phenylethynylzinc Bromide to Aldehydes. Synlett 1990, 547.
85. For the enantioselective addition of zinc acetylides (generated from the corresponding lithium acetylides) to aldehydes, see: Niwa, S.; Soai, K. Catalytic Asymmetric-Synthesis of Optically-Active Alkynyl Alcohols by Enantioselective Alkynylation of Aldehydes and by Enantioselective Alkylation of Alkynyl Aldehydes. J. Chem Soc., Perkin Trans. 1 1990, 937. Tombo, G. M. R.; Didier, E.; Loubinoux, B. Amino Alcohol Mediated Enantioselective Addition of 2-Phenylethynylzinc Bromide to Aldehydes. Synlett 1990, 547.
86. For other methods see: (a) Kobayashi, S.; Furuya, M.; Ohtsubo, A.; Mukaiyama, T. Catalytic Asymmetric Aldol Reaction of the Silyl Enol Ether of Acetic-Acid Thioester with Aldehydes Using Chiral Tin(II) Lewis Acid. Tetrahedron: Asymmetry 1991, 2, 635.
87. (b) Carreira, E. M.; Singer, R. A.; Lee, W. Catalytic, Enantioselective Aldol Additions with Methyl and Ethyl-Acetate O-Silyl Enolates -A Chiral Tridentate Chelate as a Ligand for Titanium(IV). J. Am. Chem. Soc. 1994, 116, 8837.
88. (c) Singer, R. A.; Shepard, M. S.; Carreira, E. M. Catalytic, Enantioselective Acetate Aldol Additions to α,β-Ynals: Preparation of Optically Active Propargylic Alcohols Tetrahedron 1998, 54, 7025.
89. Corey, E. J.; Cimprich, K. A. Highly Enantioselective Alkynylation of Aldehydes Promoted by Chiral Oxazaborolidines. J. Am. Chem. Soc. 1994, 116, 3151.
90. Hendrickson, J. B. Systematic Synthesis Design. 6. Yield Analysis and Convergency. J. Am. Chem. Soc. 1977, 99, 5439.
91. The following list of amino alcohols examined is representative: 1-(dimethylamino)indan-2-ol, 2-(N, N-dimethylamino)-1,2-diphenylethanol, 2-(N, N-dimethylamino)-1, 1-diphenylpropanol, (1-methyl-pyrrolidin-2-yl)-methanol, 2′-(dimethylamino)-1,1′-binaphthalenyl-2-ol, 2-dibutylamino-1-phenyl-propan-1-ol, and 1-phenyl-2-pyrrolidin-1-ylpropan-1-ol.
92. Frantz, D. E.; Fässler, R.; Carreira, E. M. Facile Enantioselective Synthesis of Propargylic Alcohols by Direct Addition of Terminal Alkynes to Aldehydes. J. Am. Chem. Soc. 2000, 122, 1806.
93. Noyori, R. Asymmetric Catalysis in Organic Synthesis; Wiley: New York, 1994; Chapter 5.
94. In preliminary studies we have observed that the process displays positive nonlinear behavior. Thus, when 4-phenyl-1-butyne was added to cyclohexanecarboxaldehyde in the presence of N-methylephedrine (20% ee), the resulting propargylic alcohol was isolated in 39% ee.
95. (a) Dagoneau, C.; Denis, J.-N.; Vallée, Y. Synthesis of Z-α,β-Ethylenic N-Boc-Gamma-Amino Esters from Nitrones. Synlett 1999, 602.
96. (b) Merino, P.; Franco, S.; Merchan, F. L.; Tejero, T. Asymmetric Addition Reactions of Lithium (Trimethylsilyl) Acetylide with Chiral α-Amino Nitrones. Synthesis of Diastereomerically Pure N-Hydroxy-α-Amino Acids. J. Org. Chem. 1998, 63, 5627.
97. (c) Merino, P.; Castillo, E.; Franco, S.; Merchan, F. L.; Tejero, T. Ready Access to Enantiopure 5-Substituted-3-Pyrrolin-2-Ones from N-Benzyl-2,3-O-Isopropylidene-D-Glyceraldehyde Nitrone (BIGN). Tetrahedron: Asymmetry 1998, 9, 1759.
98. (d) Merino, P.; Anoro, S.; Castillo, E.; Merchan, F.; Tejero, T. Direct Vinylation and Ethynylation of Nitrones, Stereodivergent Synthesis of Allyl and Propargyl Amines. Tetrahedron: Asymmetry 1996, 7, 1887.
99. For a recent report of the addition of silyl ketene acetals to nitrones, see: Ohtake, H.; Imada, Y.; Murahashi, S. I. Highly Diastereoselective Addition of a Chiral Ketene Silyl Acetal to Nitrones: Asymmetric Synthesis of β-Amino Acids and Key Intermediates of β-Lactam Antibiotics. J. Org. Chem. 1999, 64, 3790.
100. For highly diastereoselective additions to chiral ketimines, see: (a) Cogan, D. A.; Ellman, J. A. Asymmetric Synthesis of α,α-Dibranched Amines by the Trimethylaluminum-Mediated 1,2-Addition of Organolithiums to Tert-Butanesulfinyl Ketimines. J. Am. Chem. Soc. 1999, 727, 268.
101. (b) Liu, G.; Cogan, D.; Ellman, J. A. Catalytic Asymmetric Synthesis of Tert-Butanesulfinamide. Application to the Asymmetric Synthesis of Amines. J. Am. Chem. Soc. 1997, 119, 9913.
102. (c) Cogan, D. A.; Liu, G.; Kim, K.; Backes, B. J.; Ellman, J. A. Catalytic Asymmetric Oxidation of Tert-Butyl Disulfide. Synthesis of Tert-Butanesulfinamides, Tert-Butyl Sulfoxides, and Tert-Butanesulfinimines. J. Am. Chem. Soc. 1998, 720, 8011.
103. (d) Davis, F. A.; Zhou, P.; Chen, B.-C. Asymmetric Synthesis of Amino Acids Using Sulfinimines (Thiooxime S-Oxides). Chem. Soc. Rev. 1998, 27, 13.
104. For recent reports of additions to nitrones, see: (e) Ukaji, Y.; Kenmoku, Y.; Inomata, K. Asymmetric Addition Reaction of Organozinc Reagents to Nitrones Using a Catalytic Amount of External Chiral Auxiliary. Tetrahedron: Asymmetry 1996, 7, 53.
105. (f) Ukaji, Y.; Shimizu, Y.; Kenmoku, Y.; Ahmed, A.; Inomata, K. Catalytic Asymmetric Addition Reaction of Dialkylzinc to Nitrone Utilizing Tartaric Acid Ester as a Chiral Auxiliary. Chem. Lett. 1997, 57.
106. (g) Ukaji, Y.; Shimizu, Y.; Kenmoku, Y.; Ahmed, A.; Inomata, K. Catalytic Asymmetric Addition of Dialkylzinc to 3,4-Dihydroisoquinoline N-Oxides Utilizing Tartaric Acid Ester as a Chiral Auxiliary. Bull. Chem. Soc. Jpn. 2000, 73, 447.
107. (h) Ukaji, Y.; Yoshida, Y.; Inomata, K. Asymmetric Addition of a Reformatsky-Type Reagent to 3,4-Dihydroisoquinoline N-Oxides. Tetrahedron: Asymmetry 2000, 11, 733.
108. Frantz, D. E.; Fässler, R.; Carreira, E. M. Catalytic In Situ Generation of Zn(II)-Alkynilides under Mild Conditions: A Novel C=N Addition Process Utilizing Terminal Acetylenes. J. Am. Chem. Soc. 1999, 121, 11245.
109. The use of (S)-O-(1-phenylbutyl)carboxaldehyde aldoximes for highly diastereoselective nucleophilic additions of organolithiums been reported by Moody, see Moody, C. J.; Hunt, J. C. A. Addition of 2-Lithiothiazoles to Rophy/Sophy Aldoximes: Asymmetric Synthesis of 1-(2-Thiazolyl) Ethylamines. Synlett 1999, S1, 984.