Unexpected cis-Selectivity in (Sylvestre) Julia Olefinations with Bu₃Sn-Containing Allyl Benzothiazolyl Sulfones: Stereoselective Synthesis of 1,3-Butadienyl- and 1,3,5-Hexatrienylstannanes

Abstract

Bu₃Sn-substituted benzothiazolyl sulfones 1c, 1d, and 1f were subjected to Julia olefination reactions with a variety of aldehydes. cis-Selectivities up to 97:3 were obtained by using KHMDS as base in THF.

alkenylstannanes - dienes - Julia-Lythgoe olefination - stereoselectivity - trienes

References

1a First report: Julia M. Paris J.-M. Tetrahedron Lett.  1973,  4833 

1b Stereochemical investigations: Kocienski PJ. Lythgoe B. Ruston S. J. Chem. Soc., Perkin Trans. 1  1978,  829 

1c Kocienski PJ. Lythgoe B. Waterhouse I. J. Chem. Soc., Perkin Trans. 1  1980,  1045 

2a A cis-selective variant of the (Marc) Julia-Lythgoe olefination was reported, too: Bremmer J. Julia M. Launay M. Stacino JP. Tetrahedron Lett.  1982,  23:  3265 

2b Julia M. Lauron H. Stacino JP. Verpeaux JN. Jeannin Y. Dromzee Y. Tetrahedron  1986,  42:  2475 

2c Select applications: Julia M. Stacino JP. Tetrahedron  1986,  42:  2469 

2d Cuvigny T. Dupenhoat CH. Julia M. Tetrahedron  1987,  43:  859 

2e Holmes AB. Pooley GR. Tetrahedron  1992,  48:  7775 

3a First report: Baudin JB. Hareau G. Julia SA. Ruel O. Tetrahedron Lett.  1991,  32:  1175 

3b Stereochemical studies: Baudin JB. Hareau G. Julia SA. Ruel O. Bull. Soc. Chim. Fr.  1993,  130:  336 

3c Baudin JB. Hareau G. Julia SA. Lorne R. Ruel O. Bull. Soc. Chim. Fr.  1993,  130:  856 

3d For an exception see: Bellingham R. Jarowicki K. Kocienski P. Martin V. Synthesis  1996,  285 : A 71:29 cis:trans ratio was observed for the hexatrienes resulting from an a-lithioallyl benzothiazolyl sulfone and an a,b-unsaturated aldehyde. This ratio was increased to 82:18 employing the a-potassioallyl benzothiazolyl sulfone

3e Note added in proof: A 75:25 cis:trans ratio has been published recently for the (Sylvestre) Julia olefination of a multiply conjugated aldehyde with an α-sodiopentadienyl benzothiazolyl sulfone: Furuichi N. Hara H. Osaki T. Nakano M. Mori H. Katsumura S. J. Org. Chem.  2004,  69:  7949 

4 (Sylvestre) Julia olefinations with the sodium derivatives of cyclopropylcarbinyl benzothiazolyl sulfone are a notable exception showing solvent-dependent trans:cis ratios (78:22 in DMF - 9:91 in toluene or CH₂Cl₂): Charette AB. Lebel H. J. Am. Chem. Soc.  1996,  118:  10327 

5 Modified (Sylvestre) Julia olefinations with alkyl N-phenyltetrazolyl sulfones: Blakemore PR. Cole WJ. Kocienski PJ. Morley A. Synlett  1998,  26 

6 Modified (Sylvestre) Julia olefinations with alkyl N-tert-butyltetrazolyl sulfones: Kocienski PJ. Bell A. Blakemore PR. Synlett  2000,  365 

7a Modified (Sylvestre) Julia olefinations with alkyl 2-pyridyl sulfones: Charette AB. Bethelette C. St-Martin D. Tetrahedron Lett.  2001,  42:  5149 

7b Corrigendum: Charette AB. Bethelette C. St-Martin D. Tetrahedron Lett.  2001,  42:  6619 

8 Review: Blakemore PR. J. Chem. Soc., Perkin Trans. 1  2002,  2563 

9 Kende AS. Mendoza JS. Tetrahedron Lett.  1990,  31:  7105 

10a Lankat R. Diplomarbeit   Universität Würzburg: 1992.  p.25 

10b Lankat R. Diplomarbeit   Universität Würzburg: 1992.  p.28 

11 Vaz B. Alvarez R. de Lera AR. J. Org. Chem.  2002,  67:  5040 

12a Brückner R. Siegel K. Sorg A. In Strategies and Tactics in Organic Synthesis   Vol. 5:  Harmata M. Elsevier; Amsterdam: 2004.  p.437-473  

12b

Sorg, A.; Siegel, K.; Brückner, R. Chem.-Eur. J. in press.

13

3,8-Dimethyl-1,10-bis(tributylstannyl)-1,3,5,7,9-decapentaene as a 94:6 mixture of cis-3 and trans-3: At
-78 °C KHMDS (1.0 M in THF, 0.26 mL, 0.26 mmol, 1.12 equiv) was added to a solution of sulfone 1f (147.3 mg, 0.259 mmol, 1.12 equiv) and aldehyde 2 (89.0 mg, 0.231 mmol, 1.00 equiv) in THF (1.5 mL), resulting in a purple solution. This solution was warmed to r.t. over a period of 2 h. Pentane (4 mL) and brine (2 mL) were added. The aqueous phase was extracted with pentane (2 × 2 mL) and the combined organic extracts were washed with brine (2 mL). After drying with Na₂SO₄ the solvent was removed in vacuo. Flash chromatography [Al₂O₃ (deactivated with 3% H₂O), cyclohexane: Et₃N = 200:2] afforded the title compound (142.2 mg, 63%; ref. [11] : 83%) as a 94:6 mixture of cis-3 and trans-3 as a yellow oil. IR (film): n = 2955, 2925, 2870, 2855, 1560, 1465, 1455, 1375, 1070, 1005, 980, 960, 880, 875, 865, 760, 690, 665, 595 cm^-1. ¹H NMR (499.9 MHz, C₆HD₅ as internal standard in C₆D₆): δ = ca. 0.91-1.09 (m, 6 × SnCH ₂ CH₂CH₂CH₃), in part superimposed by 0.93 (t, J _vic = 7.3 Hz, 6 × SnCH₂CH₂CH₂CH ₃ ), 1.38 (tq, both J _vic = 7.6 Hz, 6 × SnCH₂CH₂CH ₂ CH₃), 1.54-1.72 (m, 6 × SnCH₂CH ₂ CH₂CH₃), 1.87 (d, J _allyl = 0.6 Hz, 3-CH₃, 8-CH₃), 6.44 (m_c, 5-H, 6-H), 6.53 (d, J _1,2 and J _10,9 = 19.1 Hz, flanked by Sn isotope satellites as 2 interlocked d, ² J ^¹¹9 _Sn,H = 69.8 Hz, ² J ^¹¹7 _Sn,H = 66.3 Hz, 1-H, 10-H), 6.85 (br d, J _4,5 and J _7,6 = 8.2 Hz, 4-H, 7-H), 6.94 (d, J _2,1 and J _9,10 = 19.2 Hz, flanked by Sn isotope satellites as 2 interlocked d, ³ J ^¹¹9 _Sn,H = 64.9 Hz, ³ J ^¹¹7 _Sn,H = 62.1 Hz, 2-H, 9-H). ¹³C NMR (125.7 MHz, C₆HD₅ as internal standard in C₆D₆): δ = 9.89 (flanked by Sn isotope satellites as 2 d, ¹ J ^¹¹9 _{Sn,C-1 ′′} = 342.1 Hz, ¹ J ^¹¹7 _{Sn,C-1 ′′} = 327.0 Hz, SnCH₂CH₂CH₂CH₃), 12.01 (3-CH₃, 8-CH₃), 13.90 (SnCH₂CH₂CH₂ CH ₃ ), 27.69 (flanked by Sn isotope satellites as 1 d, ³ J ^¹¹9 _{Sn,C-3 ′′} = ³ J ^¹¹7 _{Sn,C-3 ′′} = 54.2 Hz, SnCH₂CH₂ CH₂CH₃), 29.58 (flanked by Sn isotope satellites as 1 d, ² J ^¹¹9 _{Sn,C-2 ′′} = ² J ^¹¹7 _{Sn,C-2 ′′} = 20.6 Hz, SnCH₂ CH₂CH₂CH₃), 126.63 (C-5, C-6), 126.93 (C-4, C-7), 128.93 (C-1, C-10), 137.95 (half intensity, C-3, C-8), 151.69 (flanked by Sn isotope satellites as 1 d, ² J ^¹¹9 _Sn,C-2 = ² J ^¹¹7 _Sn,C-2 and ² J ^¹¹9 _Sn,C-9 = ² J ^¹¹7 _Sn,C-9 = 10.9 Hz, C-2, C-9). The cis configuration of the C⁵=C⁶ double bond was proved by an edited HSQC experiment (‘¹H-coupled short-range H,C-COSY’, 499.9/125.7 MHz, C₆D₆): The ¹³C signal at δ = 126.63 (C-5/C-6), split by ¹ J _C-5,5-H = ¹ J _C-6,6-H = 155.8 Hz, revealed the H,H coupling constants J _5,4 = J _5,6 and J _6,7 =
J _6,5 = 11.2 Hz. HRMS (EI, 70 eV): m/z = 681.26813 [M⁺ - Bu], which is 3.89 ppm more than calcd for C₃₂H₅₉Sn₂ (m/z = 681.26548).

14

Sorg, A. Dissertation; Universität Freiburg, 2004.

15

All new compounds gave satisfactory ¹H NMR and ¹³C NMR spectra and provided correct combustion analyses or high resolution mass spectra.

16a H₂O₂ oxidation/Mo(VI) catalysis: Schultz HS. Freyermuth HB. Buc SR. J. Org. Chem.  1963,  28:  1140 

16b

H₂O₂ oxidation/(NH₄)₆Mo₇O₂₄ catalysis: see ref.^3b

17 Still WC. Kahn M. Mitra A. J. Org. Chem.  1978,  43:  2923 

18

Cis:trans ratios up to >99:1 for (Sylvestre) Julia olefinations of pentanal or octanal with (γ-butylpropargyl) benzothiazolyl sulfone, LiBr, and LDA in THF: see ref.^3c

19 Williams DR. Clark MP. Tetrahedron Lett.  1999,  40:  2291 

20

After terminating the present study, we learned that Professor de Lera and associates observed cis-selective (Sylvestre) Julia olefinations, too, starting from a series of polyenyl benzothiazolyl sulfones including sulfone 1f. In their study, these authors (Vaz, B.; Alvarez, R.; Souto, J. A.; de Lera, A. R. Synlett 2005, following paper) had independently revised the stereochemical outcome of their olefination 1f + 2 → 3 in favor of the selectivity depicted in Scheme [1] .

21 Rzasa RM. Shea HA. Romo D. J. Am. Chem. Soc.  1998,  120:  591 

22 Kiehl A. Eberhardt A. Adam M. Enkelmann V. Müllen K. Angew. Chem., Int. Ed. Engl.  1992,  31:  1588 ; Angew. Chem. 1992, 104, 1623

23 Brückner S. Abraham E. Klotz P. Suffert J. Org. Lett.  2002,  4:  3391 

24 Lipshutz BH. Lindsley C. J. Am. Chem. Soc.  1997,  119:  4555 

25 Siegel K. Brückner R. Synlett  1999,  1227 

26 Domon L. Uguen D. Tetrahedron Lett.  2000,  41:  5501 

27 Lipshutz BL. Lee JI. Tetrahedron Lett.  1991,  32:  7211 

28 Alvarez R. Herrero M. Lopez S. de Lera AR. Tetrahedron  1998,  54:  6793