One-step RhCl3-catalyzed deprotection of acyclic N-allyl amides

Journal of Organic Chemistry

Volumn 72, Issue 16, 2007, Pages 6298-6300

  Zacuto, Michael J ^a   Xu, Feng ^a  

^a MERCK RESEARCH LABORATORIES   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

ENAMIDES; N-ALLYL AMIDES; RHODIUM HYDRIDE;

ALCOHOLS; CATALYSIS; HYDROCHLORIC ACID; ISOMERIZATION; RHODIUM COMPOUNDS; SOLVENTS;

AMIDES;

ALCOHOL; ALKENE; ALLYL COMPOUND; AMIDE; HYDROCHLORIC ACID; N ALLYL 2 PYRROLIDONE; PYRROLE DERIVATIVE; RHODIUM; RUTHENIUM; SOLVENT; UNCLASSIFIED DRUG; ALCOHOL DERIVATIVE;

ARTICLE; CATALYSIS; DEPROTECTION REACTION; ISOMERIZATION; REACTION ANALYSIS; REACTION TIME; SYNTHESIS; TEMPERATURE; CHEMICAL MODEL; CHEMISTRY; METHODOLOGY; ORGANIC CHEMISTRY; TIME;

ALCOHOLS; AMIDES; CATALYSIS; CHEMISTRY, ORGANIC; MODELS, CHEMICAL; RHODIUM; SOLVENTS; TIME FACTORS;

EID: 34547623795     PISSN: 00223263     EISSN: None     Source Type: Journal    
DOI: 10.1021/jo070553t     Document Type: Article

References (33)

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22. Use of EtOH as a solvent resulted in a 4:1 ratio, whereas use of MeOH resulted in the exclusive formation of the N,O-acetal.
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29. 3 in the presence of alcohols and KOAc reduces nitro-arenes to anilines.
30. 1H NMR analysis of the crude reaction mixture, referring to reported characterization data of 24 and 25: Han, G.; LaPorte, M. G.; McIntosh, M. C.; Weinreb, S. M. J. Org. Chem. 1996, 61, 9483. After 10 h, the combined yield of 6 and 7 was ∼40%. When n-PrOH was used as solvent, the combined yield of the analogous products was ∼75%.
31. 2O.
32. 3, the only observed product was 1.
33. After 8 h. In the presence of HCl in PrOH, enamide 1 was rapidly converted to N,O-acetal 2, which slowly converted to the observed 2:1 mixture. In the case of lactams, the observed ratios may reflect an equilibrium. For example, see: Afinogenov, V. A.; Filimonov, V. D.; Sirotkina, E. E. Zh. Org. Khim. 1978, 14, 1723.