synthesis of pyrrole phosphonate esters: emphasis on pyrrole nh acids and dialkylacetylenic esters substitution
نویسندگان
چکیده
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.
منابع 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 31</...
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عنوان ژورنال:
iranian journal of chemistry and chemical engineering (ijcce)ناشر: iranian institute of research and development in chemical industries (irdci)-acecr
ISSN 1021-9986
دوره 27
شماره 1 2008
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