- Synthesis of isoquinoline alkaloids via oxidative amidation-bischler- napieralski reaction
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A straightforward synthesis of -keto amides by coupling primary amines with aryl dibromoethanones under oxidative amidation conditions has been developed. The -keto amides were then subjected to heterocyclodehydration reaction under Bischler-Napieralski conditions followed by aromatization with DBU provided 1-benzoyl isoquinolines in a two-stage process. Utilizing this methodology, isoquinoline alkaloids such as thalmicrinone, papavaraldine, and pulcheotine A were synthesized in excellent yields. Georg Thieme Verlag Stuttgart · New York.
- Shankar,More, Satish S.,Madhubabu,Vembu,Syam Kumar
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supporting information; experimental part
p. 1013 - 1020
(2012/06/01)
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- The Reaction of Phenylglyoxal with Primary Aliphatic and Aromatic Amines. Synthesis of Phenylglyoxal Monoimines and some Derivatives.
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Condensation of phenylglyoxal with primary aliphatic amines yields the related keto-aldimines.When primary aromatic amines are used, aldimines, amino-hydroxy-ketones, diamino-ketones, and alkoxy-amino-ketones are obtained depending upon the nature of the amine and the experimental conditions.Alternatively the monoimines can be obtained by dehydration of C-hydroxyphenacylarylamines and by demethanolation of C-methoxyphenacylarylamines both on treatment with Pd/C catalyst.Reduction of phenylglyoxal monoimines with sodium borohydride yielded H-substituted 1-phenyl-2-aminoethanols and 1,3-dipolar cycloaddition of the imines with p-chlorobenzonitrile oxide afforded 4-substituted 5-benzoyl-3-(p-chlorophenyl)-4,5-dihydro-1,2,4-oxadiazoles.
- Alcaide, Benito,Escobar, Gerardo,Perez-Ossorio, Rafael,Plumet, Joaquin,Sanz, Dionisia
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p. 1466 - 1488
(2007/10/02)
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