Phosphine-catalyzed intramolecular γ-umpolung addition of α-aminoalkylallenic esters: facile synthesis of 3-carbethoxy-2-alkyl-3-pyrrolines.
نویسندگان
چکیده
An array of N-tosylated α-aminoalkylallenic esters was prepared and their cyclization under the influence of nucleophilic phosphine catalysts was explored. The α-aminoalkylallenic esters were prepared through aza-Baylis-Hillman reactions or novel DABCO-mediated decarboxylative rearrangements of allenylic carbamates. Conversion of these substrates to 3-carbethoxy-2-alkyl-3-pyrrolines was facilitated through Ph(3)P-catalyzed intramolecular γ-umpolung addition.
منابع مشابه
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ورودعنوان ژورنال:
- Chemical communications
دوره 48 43 شماره
صفحات -
تاریخ انتشار 2012