Imine Allylations by Allylic Trichlorotins Derived from α,α-Diisopropylhomoallylic Alcohols with Tin(II) Chloride and N-Chlorosuccinimide

Abstract

Allylic trichlorotins, prepared in situ from α,α-diisopropylhomoallylic alcohols with tin(II) chloride and N-chlorosuccinimide in dichloromethane at -40 ºC, cause nucleophilic addition to N-tosylimines or N-tosyliminiums to afford the corresponding α-substituted homoallylic amines.

nucleophilic additions - allylations - organometallic reagents - allylic tins - homoallylic amines

References

1 For a review, see: Yamamoto Y. Asao N. Chem. Rev.  1993,  93:  2207 

For recent non-Barbier-type imine allylations using imines, iminiums, oximes, hydrazones and so on, see:

2a Kise N. Yamazaki H. Mabuchi T. Shono T. Tetrahedron Lett.  1994,  35:  1561 

2b Hoffman RV. Nayar NK. Shankweiler JM. Klinekole BW. Tetrahedron Lett.  1994,  35:  3231 

2c Panek JS. Jain NF. J. Org. Chem.  1994,  59:  2674 

2d Basile T. Bocoum A. Savoia D. Umani-Ronchi A. J. Org. Chem.  1994,  59:  7766 

2e Bellucci C. Cozzi PG. Umani-Ronchi A. Tetrahedron Lett.  1995,  36:  7289 

2f Wang D.-K. Dai L.-X. Hou X.-L. Tetrahedron Lett.  1995,  36:  8649 

2g Veenstra SJ. Schmid P. Tetrahedron Lett.  1997,  38:  997 

2h Kobayashi S. Iwamoto S. Nagayama S. Synlett  1997,  1099 

2i Billet M. Klotz P. Mann A. Tetrahedron Lett.  2001,  42:  631 

2j Hirabayashi R. Ogawa C. Sugiura M. Kobayashi S. J. Am. Chem. Soc.  2001,  123:  9493 

2k Aspinall HC. Bissett JS. Greeves N. Levin D. Tetrahedron Lett.  2002,  43:  323 

For Barbier-type imine allylations, see:

3a Chan TH. Lu W. Tetrahedron Lett.  1998,  39:  8605 

3b Lu W. Chan TH. J. Org. Chem.  2000,  65:  8589 

3c Vilaivan T. Winotapan C. Shinada T. Ohfune Y. Tetrahedron Lett.  2001,  42:  9073 

3d Wallner OA. Szabó KJ. Org. Lett.  2002,  4:  1563 

4a Masuyama Y. J. Synth. Org. Chem. Jpn.  1992,  50:  202 

4b Masuyama Y. In Advances in Metal-Organic Chemistry   Vol. 3:  Liebeskind LS. JAI Press; Greenwich: 1994.  p.255 

4c Masuyama Y. In Recent Research Developments in Organic Chemistry   Vol. 4:  Transworld Research Network; Trivandrum, India: 2000.  p.373 ; and references cited therein

5

The use of imines such as N-benzylideneaniline and N-benzylidenetosylamide in the allylation with tin(II) halides did not afford homoallylic amines but homoallylic alcohols in low yields.

6

Tin(II) chloride is insoluble in dichloromethane, and dissolves in dichloromethane containing an equimolar amount of alcohol to the tin(II) by adding an equimolar amount of NCS to the tin(II).

7a Tagliavini G. Rev. Silicon, Germanium, Tin, Lead  1985,  8:  237 

7b Jones P. Knochel P. J. Org. Chem.  1999,  64:  186 ; and references cited therein

8 Masuyama Y. Saeki K. Horiguchi S. Kurusu Y. Synlett  2001,  1802 

9 Masuyama Y. Tosa J. Kurusu Y. Chem. Commun.  1999,  1075 

10

The syn-diastereoselectivity in the allylations by 5 was confirmed by the comparison of ¹H NMR spectra with authentic samples prepared by the imine allylation by 1-bromo-2-butene with indium. [3] In addition the diastereo-selectivity in ref. [9] has been mistaken; syn adducts are major, similarly to the imine allylation by 5.

11

The E:Z ratio of A could not be determined by the ¹H NMR observation of the reaction of 5 with SnCl₂ and NCS in CD₂Cl₂ either at -40 ºC or at room temperature. Since the E:Z ratios of α-adducts in the carbonyl allylation by 5 are ca. 1:1 to 1:4, [8] the 2-butenyltrichlorotin intermediate is presumed to be an E,Z mixture.