New S,O-acetals From (1R)-(-)-Myrtenal as Chiral Auxiliaries in Nucleophilic Additions
Peréz Estrada, Salvador
2004
Chacón-García, L.; Lagunas-Rivera, S.; Pérez-Estrada, S.; Vargas-Díaz, M. E.; Joseph-Nathan, P.; Tamariz, J.; Zepeda, L. G. ?New S,O-acetals From (1R)-(-)-Myrtenal as Chiral Auxiliaries in Nucleophilic Additions? Tetrahedron Lett. 2004, 45, 2141-2145, DOI: 10.1016/j.tetlet.2004.01.046.
Abstract
Treatment of hydroxythiol 4 with ?,?-diethoxyacetophenone at room temperature yielded a mixture of epimeric S,O-acetals 6 and 7 (1:4, 92% yield), which were efficiently separated by flash chromatography. The OTBS derivatives 8 and 9 were treated with several Grignard reagents to afford carbinols 10 and 13 respectively (85?99% yield, >95% dr). After successive hydrolysis and reduction of 10 and 13 it is possible to obtain either enantiomer of diols 16 in high optical purity (>95% er).
