@article { ISI:000327175500054,
	title = {Reactivity umpolung in intramolecular ring closure of 3,4-disubstituted butenolides: diastereoselective total synthesis of paeonilide},
	journal = {Organic Letters},
	volume = {15},
	number = {22},
	year = {2013},
	month = {NOV},
	pages = {5826-5829},
	publisher = {AMER CHEMICAL SOC},
	address = {1155 16TH ST, NW, WASHINGTON, DC 20036 USA},
	abstract = {<p>Remarkable reactivity reversal stratagem in 3,4-disubstituted butenolides under acidic conditions is described. Design of a suitably substituted multifunctional butenolide followed by an acid-catalyzed chemo- and diastereoselective intramolecular ring closure via the reactivity umpolung has been demonstrated to accomplish a concise total synthesis of paeonilide. Overall, the present protocol involves one-pot reduction of an a,alpha,beta-unsaturated carbon carbon double bond and intramolecular nucleophilic insertion of oxygen function at the electron-rich gamma-position of butenolide. The involved mechanistic aspects have also been discussed.</p>},
	issn = {1523-7060},
	doi = {10.1021/ol4028804},
	author = {Deore, Prashant S. and N. P. Argade}
}
