The natural product (-)-N-methylwelwitindolinone C isothiocyanate is isolated from a blue-green algae and has been identified as a promising compound to treat drug-resistant tumors. Compound X (R = protecting group) was utilized as a key synthetic intermediate in the synthesis of the natural product (J. Am. Chem. Soc. 2011, 133, 15797-15799). Compound X can be prepared in a ring-forming reaction from compound Y under strongly basic conditions (excess NaNH2), as illustrated in the following retrosynthetic scheme: CI N-methyl- welwitindolinone C Isothiocyanate SCN ° H RO Several steps OR H H 0 Propose a plausible mechanism for conversion of Y into X under basic conditions. For the mechanism, draw the curved arrows as needed. Include lone pairs and charges in your answer. Do not draw out any hydrogen explicitly in your products. Do not use abbreviations such as Me or Ph.

The natural product (-)-N-methylwelwitindolinone C isothiocyanate is isolated from a blue-green algae and has been identified as a promising compound to treat drug-resistant tumors. Compound X (R = protecting group) was utilized as a key synthetic intermediate in the synthesis of the natural product (J. Am. Chem. Soc. 2011, 133, 15797-15799). Compound X can be prepared in a ring-forming reaction from compound Y under strongly basic conditions (excess NaNH2), as illustrated in the following retrosynthetic scheme: CI N-methyl- welwitindolinone C Isothiocyanate SCN ° H RO Several steps OR H H 0 Propose a plausible mechanism for conversion of Y into X under basic conditions. For the mechanism, draw the curved arrows as needed. Include lone pairs and charges in your answer. Do not draw out any hydrogen explicitly in your products. Do not use abbreviations such as Me or Ph.

Organic Chemistry

8th Edition

ISBN:9781305580350

Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. Foote

Publisher:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. Foote

Chapter22: Reactions Of Benzene And Its Derivatives

Section: Chapter Questions

Problem 22.59P

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