metal-free intramolecular dearomative annulation reaction of 2-pyridylacetate derivatives has been successfully developed under mild conditions, affording structurally diverse substituted 3,4-dihydroquinolizin-2-ones decorated with a range of functional groups in moderate to good yields. The key to the success of this reaction is the existence of the substrates 2-pyridylacetate derivatives in complete
‘One-pot’ organocatalyzed enantioselective synthesis of highly functionalized 3,4,5,6-tetrasubstituted dihydropyrans by sequential Knoevenagel condensation/Michael addition and hemiacetalization
作者:Ajay R. Tilekar、Arun R. Jagdale、Gagan Kukreja、G. Gautham Shenoy、Neelima Sinha
DOI:10.1016/j.tetasy.2016.10.014
日期:2017.1
An organocatalytic 'one-pot' synthesis of highly functionalized 3,4,5,6-tetrasubstituted dihydropyrans has been developed. Excellent enantio- and diastereo selectivity with good yields are some of the salient features of this methodology. This reaction takes advantage of proline based catalysts and follows stepwise sequential transformations including Knoevenagel condensation-Michael addition-hemiacetalization towards the synthesis of complex dihydropyranol framework. (C) 2016 Elsevier Ltd. All rights reserved.