Synthesis of Pyrrole Phosphonate Esters: Emphasis on Pyrrole NH Acids and Dialkylacetylenic Esters Substitution
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چکیده مقاله:
Reaction of dialkyl acetylenedicarboxylates 1a-c andpyrrole derivatives 2a-e in the presence of triphenylphosphite (TPP) was investigated and the effect of the pyrrole substitution was established. Diastereoselectivity is observed with pyrroles, 2a,b, yieldingphosphonate ester derivatives 3a-f and 4,and their relative configuration is determined by 1H/13C and 31P NMR and confirmed by single X-ray diffraction. Similar reactions with higher degree of substitution of the pyrrole, 2c,e showed no diastereoselectivity.
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ورودمنابع مشابه
synthesis of pyrrole phosphonate esters: emphasis on pyrrole nh acids and dialkylacetylenic esters substitution
reaction of dialkyl acetylenedicarboxylates 1a-c andpyrrole derivatives 2a-e in the presence of triphenylphosphite (tpp) was investigated and the effect of the pyrrole substitution was established. diastereoselectivity is observed with pyrroles, 2a,b, yieldingphosphonate ester derivatives 3a-f and 4,and their relative configuration is determined by 1h/13c and 31p nmr and confirmed by single x-r...
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عنوان ژورنال
دوره 27 شماره 1
صفحات 105- 113
تاریخ انتشار 2008-03-01
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