Reagent-controlled regiodivergent intermolecular cyclization of 2-aminobenzothiazoles with β-ketoesters and β-ketoamides
2017 ◽
Vol 13
◽
pp. 2739-2750
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Keyword(s):
Two regiodivergent approaches to intermolecular cyclization of 2-aminobenzothiazoles with β-ketoesters and amides have been developed, controlled by the reagents employed. With the Brønsted base KOt-Bu and CBrCl3 as radical initiator, benzo[d]imidazo[2,1-b]thiazoles are synthesized via attack at the α-carbon and keto carbon of the β-ketoester moiety. In contrast, switching to the Lewis acid catalyst, In(OTf)3, results in the regioselective nucleophilic attack at both carbonyl groups forming benzo[4,5]thiazolo[3,2-a]pyrimidin-4-ones instead.
2020 ◽
2020 ◽
Keyword(s):
2001 ◽
Vol 40
(15)
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pp. 2881-2884
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1993 ◽
Vol 459
(1-2)
◽
pp. 107-115
◽
2019 ◽
Vol 29
◽
pp. 172-178
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Keyword(s):