Steric effects in the synthesis of ortho-substituted 1,1'-binaphthalene derivatives by the SRN1 and the Stille Reactions.

BAUMGARTNER, M.T.*; TEMPESTI, TOMAS C.; PIERINI, A.B.

Arkivoc

arkat-usa

Año: 2003 vol. X p. 420 - 433

1424-6376

The scope of the SRN1 mechanism and the Stille reaction to synthesize 1,1´-binaphthalene derivatives was investigated. The best yield of 2´-methoxy-1,1´-binaphthalenyl-2-ol (52%) was obtained in liquid ammonia or DMSO by the SRN1 irradiated reaction of 1-iodo-2- methoxynaphthalene with the anion of 2-naphthol. A lower yield (40%) of BINOL is obtained in water with 1-iodo-2-hydroxynaphthalene as substrate when the reaction is sonicated before irradiation. The Stille reaction between (2-methoxy-1-naphthyl)-trimethylstannane and 1-iodo-2- methoxynaphthalene afforded low yields (15-11%) of the 1,1´-binaphthalene derivative. Based on AM1 and B3LYP calculations the yields of the 1,1´-binaphthalene derivatives obtained through the electron transfer SRN1 reaction can be attributed to kinetic factors of the radicalnucleophile coupling step.