@article {48722,
	title = {Divergent synthesis of oxepino-phthalides and [5,5]-oxaspirolactones through [2+2+2]- and [2+3]-annulation of alkynyl alcohols with a-ynone-esters},
	journal = {Journal of Organic Chemistry},
	volume = {88},
	year = {2023},
	month = {AUG },
	pages = {12597-12612},
	type = {Article},
	abstract = {<p>
	Unmasking the synthetic potential of alkyne functional group of alkynyl alcohols as surrogates of carbonyl compounds, herein we present the first Bronsted acid (TfOH)-catalyzed [2 + 2 + 2]-annulation of 4-pentyn-1-ols (possessing terminal alkyne) with a-ynone-esters to access tricyclic tetrahydro-oxepino-phthalides. Besides, an unprecedented synthesis of a-acetoaryl or a-alkynyl [5,5]-oxaspirolactones has been demonstrated by employing 4-pentyn-1-ols (possessing an internal alkyne) as an annulation partner, which proceeds through a divergent [2 + 3]-annulation pathway.</p>
},
	issn = {0022-3263},
	doi = {10.1021/acs.joc.3c01301},
	author = {Kambale, Digambar A. and Borade, Balasaheb R. and Vinodkumar, Ramavath and Kontham, Ravindar}
}
@article {49028,
	title = {Divergent access to polycyclic spiro- and fused-N,O-ketals through Bi(OTf)3-catalyzed [4+2]-annulation of cyclic N-sulfonyl ketimines and alkynols},
	journal = {Chemical Communications},
	volume = {60},
	year = {2024},
	month = {JAN},
	pages = {1144-1147},
	type = {Article},
	abstract = {<p>
	Bismuth(iii) triflate-catalyzed [4+2]-annulation of cyclic N-sulfonyl ketimines (derived from saccharin) and alkynyl alcohols (4-pentyn-1-ols and 5-hexyn-1-ols) has been reported. This cascade annulation provides a diverse array of polycyclic spiro-and-fused N,O-ketals with excellent substrate scope, good isolated yields, and diastereoselectivities under mild reaction conditions.</p>
},
	issn = {1359-7345},
	doi = {10.1039/d3cc05599j},
	author = {Nakate, Ashwini K. and Kataria, Priyanka and Sambherao, Pooja I. and Krishna, Gamidi Rama and Kontham, Ravindar}
}
