Download PDF
Synlett 2008(14): 2183-2187  
DOI: 10.1055/s-2008-1078011
LETTER
© Georg Thieme Verlag Stuttgart ˙ New York

The Conversion of Carbonyl Compounds into Pentadienylamines by a Julia-Kocienski Olefination Procedure

Reyhan Bastin, Mélanie Liron, Richard J. K. Taylor*
Department of Chemistry, University of York, Heslington, York, YO10 5DD, UK
Fax: +44(1904)434523; e-Mail: rjkt@york.ac.uk;
Further Information

Publication History

Received 23 June 2008
Publication Date:
31 July 2008 (online)

    Permissions and Reprints All articles of this category

Abstract

Julia-Kocienski olefination has been successfully employed to convert carbonyl compounds into the corresponding Boc-protected 1,3-pentadienyl amines in a C4N homologation process. Good to excellent yields are achieved in THF using MHMDS as base to deprotonate the precursor 1-phenyl-1H-tetrazol-5-ylsulfone reagent. The nature of the metallic countercation dramatically affects the stereoselectivity of the newly formed alkene: good levels of 2E,4E-stereoselectivity are achieved using KHMDS whereas LiHMDS gives a predominance of the 2E,4Z-dienyl product.

Key words

1,3-pentadienyl amines - modified Julia olefination - alkenes - 1-phenyl-1H-tetrazol-5-yl sulfones

    References and Notes

  • 1 Dvorak CA. Schmitz WD. Poon DJ. Pryde DC. Lawson JP. Amos RA. Meyers AI. Angew. Chem. Int. Ed.  2000,  39:  1664 ; and references therein
    CrossrefPubMedGoogle Scholar
  • 2 Kingston DGI. Kolpak MX. LeFevre JW. Borup-Grochtmann I. J. Am. Chem. Soc.  1983,  105:  5106 
    Google Scholar
  • 3 Maehr H. Leach M. Williams TH. Blount JF. Can. J. Chem.  1980,  58:  501 
    CrossrefGoogle Scholar
  • 4 Mori T. Takahashi K. Kashiwabara M. Uemura D. Katayama C. Iwadare S. Shizuri I. Mitomo R. Nakano F. Matsuzaki A. Tetrahedron Lett.  1985,  26:  1073 
    CrossrefGoogle Scholar
  • 5 Takahashi K. Kawabata M. Uemura D. Iwadare S. Mitomo R. Nakano F. Matsuzaki A. Tetrahedron Lett.  1985,  26:  1077 
    CrossrefGoogle Scholar
  • 6a Ryu G. Kim S.-K. J. Antibiot.  1999,  52:  193 
    Google Scholar
  • 6b Otani T. Yoshida K.-I. Kubota H. Kawai S. Ito S. Hori H. Ishiyama T. Oki T. J. Antibiot.  2000,  53:  1397 
    Google Scholar
  • 6c Manam RR. Teisan S. White DJ. Nicholson B. Grodberg J. Neuteboom STC. Lam KS. Mosca DA. Lloyd GK. Potts BCM. J. Nat. Prod.  2005,  68:  240 
    Google Scholar
  • 7a Papillon JPN. Taylor RJK. Org. Lett.  2000,  2:  1987 
    Google Scholar
  • 7b Papillon JPN. Taylor RJK. Abstracts of Papers, 222nd Meeting of the American Chemical Society, Chicago IL, Aug 26-30, 2001   American Chemical Society; Washington DC: 2001. 
    Google Scholar
  • 7c Papillon JPN. Taylor RJK. Org. Lett.  2002,  4:  119 
    Google Scholar
  • 7d See also: Webb MR. Donald C. Taylor RJK. Tetrahedron Lett.  2006,  47:  549 
    Google Scholar
  • 8 Connell RD. Helquist P. Åkermark B. J. Org. Chem.  1989,  54:  3359 ; this group also developed the phthalimide variant of reagent 8.
    Google Scholar
  • 9 Baudin JB. Hareau BG. Julia SA. Ruel O. Tetrahedron Lett.  1991,  32:  1175 
    CrossrefGoogle Scholar
  • 10a Blakemore PR. Cole WJ. Kocienski PJ. Morley A. Synlett  1998,  26 
    Google Scholar
  • 10b Kocienski PJ. Bell A. Blakemore PR. Synlett  2000,  365 
    Google Scholar
  • 10c See also: Pospisil J. Markó IE. Org. Lett.  2006,  8:  5983 
    Google Scholar
  • 11 For a review of the MJO, see: Blakemore PR. J. Chem. Soc., Perkin Trans. 1  2002,  2563 ; and references therein
    CrossrefGoogle Scholar
  • For recent applications in natural product synthesis, see:
  • 12a trans-Vaccenic acid: Duffy PE. Quinn SM. Roche HM. Evans P. Tetrahedron  2006,  62:  4838 
    Google Scholar
  • 12b [(-)-Sagittamide A: Lievens SC. Molinski TF. J. Am. Chem. Soc.  2006,  128:  11764 
    Google Scholar
  • 12c Piericidin A1 and B1: Schnermann MJ. Romero FA. Hwang I. Nakamaru-Ogiso E. Yagi T. Boger DL. J. Am. Chem. Soc.  2006,  128:  11799 
    Google Scholar
  • 12d Iejimalide B: Fürstner A. Aïssa C. Chevrier C. Teply F. Nevado C. Tremblay M. Angew. Chem. Int. Ed.  2006,  45:  5832 
    Google Scholar
  • 12e Cylindramide: Cramer N. Buchweitz M. Laschat S. Frey W. Baro A. Mathieu D. Richter C. Schwalbe H. Chem. Eur. J.  2006,  12:  2488 
    Google Scholar
  • 12f Macrolide FD-891: Garcia-Fortanet J. Murga M. Carda J. Marco JA. Matesanz R. Diaz JF. Barasoain I. Chem. Eur. J.  2007,  13:  5060 
    Google Scholar
  • 13a Takano D. Nagamitsu T. Ui H. Shiomi K. Yamaguchi Y. Masuma R. Kuwajima I. Omura S. Org. Lett.  2001,  3:  2289 
    Google Scholar
  • 13b Schultz HS. Freyermuth HB. Buc SR. J. Org. Chem.  1963,  28:  1140 
    Google Scholar
  • 15 Hilpert H. Wirz B. Tetrahedron  2001,  57:  681 
    CrossrefGoogle Scholar
14

Preparation of tert -Butyl ( E )-4-(1-Phenyl-1 H -tetrazol-5-ylsulfonyl)but-2-enyl Carbamate (11) To a solution of the sulfide 10 (7 g, 15.6 mmol) and Mo7O24 (NH4)6˙4H2O (5.8 g, 4.7 mmol) in MeOH (130 mL) was added 30% aq H2O2 (48.3 mL, 468 mmol) at r.t. The solution was stirred for 1 h, and then sat. aq Na2S2O7 solution was added to quench the excess of peroxide. After a stirring for 45 min at r.t., the reaction mixture was extracted with EtOAc (3 × 100 mL), dried (NaSO4), and concentrated in vacuo; purification by silica flash column chromatography (PE-EtOAc, 1:1) gave the title sulfone 11 (5.6 g, 95%) as a white solid, mp 86 ˚C; R f  = 0.56 (PE-EtOAc, 1:1). ¹H NMR (400 MHz, CDCl3): δ = 1.43 (s, 9 H, t-Bu), 3.77 (m, 2 H, CH2-1), 4.41 (d, J = 7.5 Hz, 2 H, CH2-4), 4.63 (br s, 1 H, NH), 5.29-6.04 (m, 1 H, H-2), 6.00 (dt, J = 15.0, 7.5 Hz, 1 H, H-3), 7.57-7.60 (m, 5 H, Ar). ¹³C NMR (100 MHz, CDCl3): δ = 28.7, 42.2, 59.5, 81.5, 114.5, 125.5, 130.0, 131.8, 133.3, 141.1, 153.4, 155.9. IR (neat): νmax = 3356, 2978, 1709, 1502, 1347, 1249, 1155 cm-¹. HRMS: m/z calcd for C16H21N5O4S [MH+]: 380.13925; found (CI): 380.1392 (0.1 ppm error).

16

The Julia-Kocienski olefination is normally trans-selective due to the kinetically controlled and irreversible addition of metallated PT-sulfones to aldehydes preferentially generating anti-β-alkoxysulfones, which then undergo Smile rearrangement. [¹0] [¹¹] In the present study, it would appear that LiHMDS preferentially generates syn-β-alkoxysulfones resulting in a predominance of the E,Z-adducts. The reasons for this unexpected switch are not fully understood at the present time but further studies are in progress to shed light on this interesting observation.

17

Preparation of 1-[ N -( tert -Butoxycarbonyl)amino]-5-phenylpenta-2,4-diene (12)
To as stirred solution of PT-sulfone 11 (45 mg, 0.12 mmol, 1.2 equiv) in THF (1.4 mL) was added LiHMDS (0.26 mL 1.0 M in THF, 0.26 mmol, 2.55 equiv), or KHMDS (0.52 mL, 0.5 M in toluene, 0.26 mmol, 2.55 equiv), at -78 ˚C. In the KHMDS case, 18-crown-6 (34 mg, 0.13 mmol, 1.2 equiv) was also present at the outset. After 1.5 h at the same temperature, the orange mixture was added to benzaldehyde (10.6 mg, 0.1 mmol, 1.0 equiv) in THF (0.9 mL) at -78 ˚C via cannula. The mixture was stirred at -78 ˚C for 1.5 h and then for 1 h at r.t. After quenching with brine (3 mL) and stirring at r.t. for 10 min, the aqueous layer was extracted with EtOAc (3 × 8 mL). The combined organic phases were dried over MgSO4 and concentrated in vacuo. Purification was performed via flash chromatography on SiO2 using mixtures of PE and EtOAc as eluent to afford the product alkenes as mixtures of their 2E,4E/2E,4Z isomers (ratio was determined by ¹H NMR spectroscopy).
Using KHMDS
72% (2E,4E/2E,4Z = 72:28); NMR data for major isomer 12 E,E were comparable to those published.8 Using LiHMDS
72% (2E,4E/2E,4Z = 13:87) as a pale yellow solid, R f  = 0.71 (PE-EtOAc, 4:1); mp 42 ˚C. ¹H NMR (400 MHz, CDCl3; major isomer): δ = 1.43 (s, 9 H, t-Bu), 3.81 (m, 2 H, H-1), 4.58 (br s, 1 H, NH), 5.84 (dt, 1 H, J = 15.0, 5.5 Hz, H-2), 6.23 (t, 1 H, J = 11.6 Hz, H-4), 6.23 (t, 1 H, J = 11.5 Hz,
H-4), 6.42 (d, 1 H, J = 11.5 Hz, H-5), 6.69 (dddd, J = 15.0, 11.5, 2.5, 1.5 Hz, 1 H, H-3), 7.36-7.25 (m, 5 H, Ar). ¹³C NMR (100 MHz, CDCl3; major isomer): δ = 28.1, 42.2, 81.5, 127.9, 128.5, 128.7, 129.4, 129.6, 130.9, 132.9, 137.6, 156.1. IR (neat): νmax = 3318, 2978, 1677, 1531, 1365, 1275, 1166, 995 cm-¹. HRMS: m/z calcd for C16H21NNaO2 [MNa]+: 282.1470; found: 282.1465 (3.5 ppm error)].

18

All novel compounds were fully characterised (sometimes as E,E/E,Z mixtures) including confirmation by high-field NMR and HRMS.