Highly Stereoselective TiCl4-Mediated Aldol Reactions from (S)-2-Benzyloxy-3-pentanone

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• 作者：Victor Rodr&iacute ; guez-Cisterna ; Cristina Villar ; Pedro Romea ; Fè ; lix Urp&iacute
• 刊名：Journal of Organic Chemistry
• 出版年：2007
• 出版时间：August 17, 2007
• 年：2007
• 卷：72
• 期：17
• 页码：6631 - 6633
• 全文大小：57K
• 年卷期：v.72,no.17(August 17, 2007)
• ISSN：1520-6904

文摘

Stereoselectivity of TiCl₄-mediated aldol reactions from(S)-2-benzyloxy-3-pentanone is dramatically improved whenthe reaction is carried out in the presence of 1.1 equiv oftetrahydrofuran (THF) or 1,2-dimethoxyethane (DME). Theresultant 2,4-syn-4,5-syn adducts are then obtained indiastereomeric ratios up to 97:3, which proves that theappropriate choice of the Lewis acid (TiCl₄-THF or DMEvs Ti(i-PrO)Cl₃) engaged in the process permits access toboth syn-aldol adducts.