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1 Results The enantioselective addition of allylic organometallic reagents to aldehydes is a fundamental tool in organic synthesis.The high degree of both diastereo-and enantioselectivity gives the possibility to obtain a wide series of homoallylic alcohols,versatile intermediates in a great number of synthesis[1]. One of the most successful approaches is related to the discovery that organocatalytic activation of the nucleophilic allyltrichlorosilanes by means of neutral Lewis bases,such as formamides,phosphoramides and pyridine N-oxides,conveniently allows allylation of aldehydes[1]. Then several efforts were addressed to the development of enantioselective versions of the reaction with the synthesis of chiral Lewis bases organocatalysts.Thus,chiral bidentate phosphoramides and N-oxides,with specific steric and electronic demands,were employed in efficient catalytic asymmetric allylations[1]. On the other hand,recently,the attention was also paid to study different neutral Lewis bases like sulfoxides[2] and phosphinoxides[3] that revealed to be efficient activators of allyltrichlorosilane.In spite of the commercial availability or of the easy synthesis,few efforts have been devoted to study in depth an enantioselective version of allylation of aldehydes in the presence of chiral sulfoxides.
1 Results The enantioselective addition of allylic organometallic reagents to aldehydes is a fundamental tool in organic synthesis. The high degree of both diastereo-and enantioselectivity gives the possibility to obtain a wide series of homoallylic alcohols, versatile intermediates in a great number of synthesis [1 One of the most successful approaches is related to the discovery that organocatalytic activation of the nucleophilic allyltrichlorosilanes by means of neutral Lewis bases, such as formamides, phosphoramides and pyridine N-oxides, convention allows allylation of aldehydes [1]. were addressed to the development of enantioselective versions of the reaction with the synthesis of chiral Lewis bases organocatalysts. Thus, chiral bidentate phosphoramides and N-oxides, with specific steric and electronic demands, were employed in efficient catalytic asymmetric allylations. [1] On the other hand, recently, the attention was also paid to study different neutral Lewis bas es like sulfoxides [2] and phosphinoxides [3] that revealed to be efficient activators of allyltrichlorosilane. In spite of the commercial availability or of the easy synthesis, few efforts have been devoted to study in depth an enantioselective version of allylation of aldehydes in the presence of chiral sulfoxides.