Nucleophilic Additions to Styrene
and Derivatives

M. Montserrat Martínez, M. Gabriela Ónega, Julio A. Seijas * , M. Pilar Vázquez-Tato #

Departamento de Química Orgánica. Facultad de Ciencias. Universidad de Santiago de Compostela.
Aptdo. 280. 27080-Lugo. Spain.


     In a preliminary communication we have reported the addition of alkyllithiums to o-vinylphenyloxazolines in good yields1. Since then there have been some reports on the addition of alkyllithium to styrene itself and substituted styrenes2. Here we want to report the actual state of our research on the reactivity of styrene like compounds with organometallic compounds.

      We carried out addition of alkyllithiums (n-BuLi, s- BuLi, t-BuLi) to o-vinylbenzoic acid and all of them added (THF, -78o C, electrophile: MeOH or MeI, 45-61% yield), however when we attempt the addition of PhLi no reaction was observed as occurred for o-vinylphenyloxazolines1. Yield obtained for o-vinylbenzoic acid were lower than those for o-vinylphenyloxazoline in all cases.



     Previously we are reporting3 than o-vinylphenyloxazolines added lithium amides. Here we report addition of lithium morpholine amide to o-vinylbenzoic acid and to styrene. We obtained addition products in both cases, 41% yield with o-vinylbenzoic acid (THF, 0o C, MeOH) and 60% with styrene (THF, r.t., MeOH), meanwhile the yield of the addition to o-vinylphenyloxazoline was 77% (THF, 0o C, MeOH). As with alkyllithium, lithium amides add in lower yield when the styrene derivatives do not bear an ortho oxazoline group.

      This results show the favourable influence of the oxazoline group in the addition.

Acknowledgement: financial support from DGICYT (PB93-0647) is gratefully acknowledged.

REFERENCES

1. J. A. Seijas, M. P. Vázquez-Tato, L. Castedo, R. J. Estévez and M. Ruíz, J. Org. Chem., 1192, 57, 5283.
2. X. Wei and J. K. Taylor, Chem. Commun., 1996, 187; and references cited there in.
3. J. A. Seijas, M. P. Vázquez-Tato et al. Communications to the 36th. IUPAC Congress. Geneva August 17-22,   1997.



* e-mail: qoseijas@lugo.usc.es
# e-mail: pilarvt@lugo.usc.es