کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
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1323934 | 977311 | 2006 | 14 صفحه PDF | دانلود رایگان |
A new method to synthesize both enantiomers of 2-diphenylphosphino-ferrocenecarboxaldehyde with the phosphine group protected as a thiophosphine group was developed. These aldehydes react with 1,2 or 1,3 diols to give, in good yields, new chiral phosphine-acetals. For unsymmetrical (R)-1,3-butanediol, the new asymmetrical acetalic carbon is asymmetric and its configuration was completely controlled by the chirality of the diol. These new P,O ligands were tested in the palladium-catalyzed asymmetric allylic substitution of 1,3-diphenylprop-2-enylacetate. Good yields and enantioselectivities up to 77% were observed. The catalytic performances of two diastereoisomeric ligands with opposite configurations in planar chirality only proved to be significantly different, showing a strong influence of both planar and central chiralities.
New chiral ferrocenyl phosphine-acetals ligands have been synthesized in an enantiomerically pure form from chiral 1,2 or 1,3-diols and the two isomers of 2-diphenylphosphino-ferrocenecarboxaldehyde. These new P,O ligands were successfully used in the palladium-catalyzed asymmetric allylic substitution of 1,3-diphenylprop-2-enylacetate with good enantioselectivities (up to 77%).Figure optionsDownload as PowerPoint slide
Journal: Journal of Organometallic Chemistry - Volume 691, Issue 10, 1 May 2006, Pages 2297–2310