کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1362259 981482 2006 12 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Stereoselective allyl transfer to chiral α-methoxycarbaldehydes: A model study related to the C-9/C-15 fragment of geldanamycin
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی آلی
پیش نمایش صفحه اول مقاله
Stereoselective allyl transfer to chiral α-methoxycarbaldehydes: A model study related to the C-9/C-15 fragment of geldanamycin
چکیده انگلیسی

The enantiomerically pure α-methoxycarbaldehyde 3 was prepared from l-leucine in five steps and 31% overall yield. The aldehyde was subjected to a diastereoselective BF3-mediated crotylation with silane 4 and to various reagent-controlled addition reactions. The configuration of aldol addition products 19 and 20 was proven by single crystal X-ray crystallography. Based on these data spectral comparison allowed an unambiguous assignment of the desired anti,syn-crotylation product 2b and of the syn,syn-crotylation product 2a. Unexpectedly, product 2a of the BF3-mediated crotylation is formally the product of chelation-control. The anti,syn-crotylation product 2b, which is a model for the C-9/C-15 fragment of geldanamycin, was obtained by a reagent-controlled crotylation with the chiral (Z)-crotylborane 23.

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ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Bioorganic & Medicinal Chemistry - Volume 14, Issue 18, 15 September 2006, Pages 6223–6234
نویسندگان
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