Influence of the protecting groups on the syn/anti stereoselectivity of boron aldol additions with erythrulose derivatives. A theoretical and experimental study

Tetrahedron

Volumn 58, Issue 48, 2002, Pages 9697-9707

  Murga, Juan ^a   Falomir, Eva ^a   González, Florenci ^a   Carda, Miguel ^a   Marco, J A ^b  

^a UNIVERSITAT JAUME I   (Spain)

^b UNIVERSITY OF VALENCIA   (Spain)

Author keywords

Ab initio calculations; Boron aldol additions; Erythrulose; Influence of protecting groups; Stereoselectivity

Indexed keywords

BENZYL DERIVATIVE; BORON DERIVATIVE; CARBOHYDRATE DERIVATIVE; CHLORINE DERIVATIVE; ERYTHRULOSE; HYDROXYL GROUP; UNCLASSIFIED DRUG;

ADDITION REACTION; ALDOL REACTION; ARTICLE; CALCULATION; CHEMICAL REACTION; CHIRALITY; EXPERIMENT; PRIORITY JOURNAL; STEREOCHEMISTRY; THEORY;

EID: 0037175549     PISSN: 00404020     EISSN: None     Source Type: Journal    
DOI: 10.1016/S0040-4020(02)01279-6     Document Type: Article

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47. There are not many alternatives in the literature for the preparation of such esters in enantiopure form. See, for example: (a) Andrus M.B., Sekhar B.B.V.S., Meredith E.L., Dalley N.K. Org. Lett. 2:2000;3035-3037 (b) Dixon D.J., Ley S.V., Polara A., Sheppard T. Org. Lett. 3:2001;3749-3752. For previous work, see references cited in these papers.
48. There are not many alternatives in the literature for the preparation of such esters in enantiopure form. See, for example: (a) Andrus M.B., Sekhar B.B.V.S., Meredith E.L., Dalley N.K. Org. Lett. 2:2000;3035-3037 (b) Dixon D.J., Ley S.V., Polara A., Sheppard T. Org. Lett. 3:2001;3749-3752. For previous work, see references cited in these papers.
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51. 2BCl (see: Walker, M. A.; Heathcock, C. H.; J. Org. Chem. 1991, 56, 5747-5750). This alternative was made unlikely by the results of Table 2 and definitively ruled out after the Z enolate configuration was secured.
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53. For discussions on mechanistic models of aldol reactions with chiral enolates, see: (a) Evans D.A., Nelson J.V., Taber T.R. Top. Stereochem. 13:1982;1-115 (b) Heathcock C.H. Aldrichim. Acta. 23:1990;99-111 (c) Van Draanen N.A., Arseniyadis S., Crimmins M.T., Heathcock C.H. J. Org. Chem. 56:1991;2499-2506 (d) Figueras S., Martín R., Romea P., Urpí F., Vilarrasa J. Tetrahedron Lett. 38:1997;1637-1640 (e) Gennari C., Moresca D., Vulpetti A., Pain G. Tetrahedron. 53:1997;5593-5608. See also Refs. 5, 18 and 22.
54. For discussions on mechanistic models of aldol reactions with chiral enolates, see: (a) Evans D.A., Nelson J.V., Taber T.R. Top. Stereochem. 13:1982;1-115 (b) Heathcock C.H. Aldrichim. Acta. 23:1990;99-111 (c) Van Draanen N.A., Arseniyadis S., Crimmins M.T., Heathcock C.H. J. Org. Chem. 56:1991;2499-2506 (d) Figueras S., Martín R., Romea P., Urpí F., Vilarrasa J. Tetrahedron Lett. 38:1997;1637-1640 (e) Gennari C., Moresca D., Vulpetti A., Pain G. Tetrahedron. 53:1997;5593-5608. See also Refs. 5, 18 and 22.
55. For discussions on mechanistic models of aldol reactions with chiral enolates, see: (a) Evans D.A., Nelson J.V., Taber T.R. Top. Stereochem. 13:1982;1-115 (b) Heathcock C.H. Aldrichim. Acta. 23:1990;99-111 (c) Van Draanen N.A., Arseniyadis S., Crimmins M.T., Heathcock C.H. J. Org. Chem. 56:1991;2499-2506 (d) Figueras S., Martín R., Romea P., Urpí F., Vilarrasa J. Tetrahedron Lett. 38:1997;1637-1640 (e) Gennari C., Moresca D., Vulpetti A., Pain G. Tetrahedron. 53:1997;5593-5608. See also Refs. 5, 18 and 22.
56. For discussions on mechanistic models of aldol reactions with chiral enolates, see: (a) Evans D.A., Nelson J.V., Taber T.R. Top. Stereochem. 13:1982;1-115 (b) Heathcock C.H. Aldrichim. Acta. 23:1990;99-111 (c) Van Draanen N.A., Arseniyadis S., Crimmins M.T., Heathcock C.H. J. Org. Chem. 56:1991;2499-2506 (d) Figueras S., Martín R., Romea P., Urpí F., Vilarrasa J. Tetrahedron Lett. 38:1997;1637-1640 (e) Gennari C., Moresca D., Vulpetti A., Pain G. Tetrahedron. 53:1997;5593-5608. See also Refs. 5, 18 and 22.
57. For discussions on mechanistic models of aldol reactions with chiral enolates, see: (a) Evans D.A., Nelson J.V., Taber T.R. Top. Stereochem. 13:1982;1-115 (b) Heathcock C.H. Aldrichim. Acta. 23:1990;99-111 (c) Van Draanen N.A., Arseniyadis S., Crimmins M.T., Heathcock C.H. J. Org. Chem. 56:1991;2499-2506 (d) Figueras S., Martín R., Romea P., Urpí F., Vilarrasa J. Tetrahedron Lett. 38:1997;1637-1640 (e) Gennari C., Moresca D., Vulpetti A., Pain G. Tetrahedron. 53:1997;5593-5608. See also Refs. 5, 18 and 22.
58. For computational studies on boron aldol reactions, see, for example: (a) Li Y., Paddon-Row M.N., Houk K.N. J. Org. Chem. 55:1990;481-493 (b) Goodman J.M., Kahn S.D., Paterson I. J. Org. Chem. 55:1990;3295-3303 (c) Bernardi A., Capelli A.M., Gennari C., Goodman J.M., Paterson I. J. Org. Chem. 55:1990;3576-3581 (d) Bernardi A., Capelli A.M., Comotti A., Gennari C., Gardner M., Goodman J.M., Paterson I. Tetrahedron. 47:1991;3471-3484 (e) Bernardi F., Robb M.A., Suzzi-Valli G., Tagliavini E., Trombini C., Umani-Ronchi A. J. Org. Chem. 56:1991;6472-6475 (f) Gennari C., Vieth S., Comotti A., Vulpetti A., Goodman J.M., Paterson I. Tetrahedron. 48:1992;4439-4458 (g) Vulpetti A., Bernardi A., Gennari C., Goodman J.M., Paterson I. Tetrahedron. 49:1993;685-696.
59. For computational studies on boron aldol reactions, see, for example: (a) Li Y., Paddon-Row M.N., Houk K.N. J. Org. Chem. 55:1990;481-493 (b) Goodman J.M., Kahn S.D., Paterson I. J. Org. Chem. 55:1990;3295-3303 (c) Bernardi A., Capelli A.M., Gennari C., Goodman J.M., Paterson I. J. Org. Chem. 55:1990;3576-3581 (d) Bernardi A., Capelli A.M., Comotti A., Gennari C., Gardner M., Goodman J.M., Paterson I. Tetrahedron. 47:1991;3471-3484 (e) Bernardi F., Robb M.A., Suzzi-Valli G., Tagliavini E., Trombini C., Umani-Ronchi A. J. Org. Chem. 56:1991;6472-6475 (f) Gennari C., Vieth S., Comotti A., Vulpetti A., Goodman J.M., Paterson I. Tetrahedron. 48:1992;4439-4458 (g) Vulpetti A., Bernardi A., Gennari C., Goodman J.M., Paterson I. Tetrahedron. 49:1993;685-696.
60. For computational studies on boron aldol reactions, see, for example: (a) Li Y., Paddon-Row M.N., Houk K.N. J. Org. Chem. 55:1990;481-493 (b) Goodman J.M., Kahn S.D., Paterson I. J. Org. Chem. 55:1990;3295-3303 (c) Bernardi A., Capelli A.M., Gennari C., Goodman J.M., Paterson I. J. Org. Chem. 55:1990;3576-3581 (d) Bernardi A., Capelli A.M., Comotti A., Gennari C., Gardner M., Goodman J.M., Paterson I. Tetrahedron. 47:1991;3471-3484 (e) Bernardi F., Robb M.A., Suzzi-Valli G., Tagliavini E., Trombini C., Umani-Ronchi A. J. Org. Chem. 56:1991;6472-6475 (f) Gennari C., Vieth S., Comotti A., Vulpetti A., Goodman J.M., Paterson I. Tetrahedron. 48:1992;4439-4458 (g) Vulpetti A., Bernardi A., Gennari C., Goodman J.M., Paterson I. Tetrahedron. 49:1993;685-696.
61. For computational studies on boron aldol reactions, see, for example: (a) Li Y., Paddon-Row M.N., Houk K.N. J. Org. Chem. 55:1990;481-493 (b) Goodman J.M., Kahn S.D., Paterson I. J. Org. Chem. 55:1990;3295-3303 (c) Bernardi A., Capelli A.M., Gennari C., Goodman J.M., Paterson I. J. Org. Chem. 55:1990;3576-3581 (d) Bernardi A., Capelli A.M., Comotti A., Gennari C., Gardner M., Goodman J.M., Paterson I. Tetrahedron. 47:1991;3471-3484 (e) Bernardi F., Robb M.A., Suzzi-Valli G., Tagliavini E., Trombini C., Umani-Ronchi A. J. Org. Chem. 56:1991;6472-6475 (f) Gennari C., Vieth S., Comotti A., Vulpetti A., Goodman J.M., Paterson I. Tetrahedron. 48:1992;4439-4458 (g) Vulpetti A., Bernardi A., Gennari C., Goodman J.M., Paterson I. Tetrahedron. 49:1993;685-696.
62. For computational studies on boron aldol reactions, see, for example: (a) Li Y., Paddon-Row M.N., Houk K.N. J. Org. Chem. 55:1990;481-493 (b) Goodman J.M., Kahn S.D., Paterson I. J. Org. Chem. 55:1990;3295-3303 (c) Bernardi A., Capelli A.M., Gennari C., Goodman J.M., Paterson I. J. Org. Chem. 55:1990;3576-3581 (d) Bernardi A., Capelli A.M., Comotti A., Gennari C., Gardner M., Goodman J.M., Paterson I. Tetrahedron. 47:1991;3471-3484 (e) Bernardi F., Robb M.A., Suzzi-Valli G., Tagliavini E., Trombini C., Umani-Ronchi A. J. Org. Chem. 56:1991;6472-6475 (f) Gennari C., Vieth S., Comotti A., Vulpetti A., Goodman J.M., Paterson I. Tetrahedron. 48:1992;4439-4458 (g) Vulpetti A., Bernardi A., Gennari C., Goodman J.M., Paterson I. Tetrahedron. 49:1993;685-696.
63. For computational studies on boron aldol reactions, see, for example: (a) Li Y., Paddon-Row M.N., Houk K.N. J. Org. Chem. 55:1990;481-493 (b) Goodman J.M., Kahn S.D., Paterson I. J. Org. Chem. 55:1990;3295-3303 (c) Bernardi A., Capelli A.M., Gennari C., Goodman J.M., Paterson I. J. Org. Chem. 55:1990;3576-3581 (d) Bernardi A., Capelli A.M., Comotti A., Gennari C., Gardner M., Goodman J.M., Paterson I. Tetrahedron. 47:1991;3471-3484 (e) Bernardi F., Robb M.A., Suzzi-Valli G., Tagliavini E., Trombini C., Umani-Ronchi A. J. Org. Chem. 56:1991;6472-6475 (f) Gennari C., Vieth S., Comotti A., Vulpetti A., Goodman J.M., Paterson I. Tetrahedron. 48:1992;4439-4458 (g) Vulpetti A., Bernardi A., Gennari C., Goodman J.M., Paterson I. Tetrahedron. 49:1993;685-696.
64. For computational studies on boron aldol reactions, see, for example: (a) Li Y., Paddon-Row M.N., Houk K.N. J. Org. Chem. 55:1990;481-493 (b) Goodman J.M., Kahn S.D., Paterson I. J. Org. Chem. 55:1990;3295-3303 (c) Bernardi A., Capelli A.M., Gennari C., Goodman J.M., Paterson I. J. Org. Chem. 55:1990;3576-3581 (d) Bernardi A., Capelli A.M., Comotti A., Gennari C., Gardner M., Goodman J.M., Paterson I. Tetrahedron. 47:1991;3471-3484 (e) Bernardi F., Robb M.A., Suzzi-Valli G., Tagliavini E., Trombini C., Umani-Ronchi A. J. Org. Chem. 56:1991;6472-6475 (f) Gennari C., Vieth S., Comotti A., Vulpetti A., Goodman J.M., Paterson I. Tetrahedron. 48:1992;4439-4458 (g) Vulpetti A., Bernardi A., Gennari C., Goodman J.M., Paterson I. Tetrahedron. 49:1993;685-696.
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68. 18,21,22 It may also be assumed that the size of these boron ligands is more decisive than its electronic nature in determining the energy of the TS of the aldol addition step. For this reason, we considered that a cyclopropyl group was a suitable model for a cyclohexyl group, even if they have different electronic features. We further considered that the dioxolane moiety of 1 (P=TMS) was an acceptable surrogate for either the bisbenzyloxyethyl fragment of 4 or the bisbenzoyloxyethyl of 6 and would simplify the calculations, as it contains fewer atoms.
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