Highly enantioselective conjugate addition of nitromethane to chalcones using bifunctional cinchona organocatalysts.

Highly enantioselective conjugate addition of nitromethane to chalcones using bifunctional cinchona organocatalysts.

Organic letters (2005-05-07)

Benedek Vakulya, Szilárd Varga, Antal Csámpai, Tibor Soós

ABSTRACT

Cinchona alkaloid-derived chiral bifunctional thiourea organocatalysts were synthesized and applied in the Michael addition between nitromethane and chalcones with high ee and chemical yields.

MATERIALI

Numero di prodotto

Marchio

Descrizione del prodotto

230731

Sigma-Aldrich

Nitromethane, ReagentPlus^®, ≥99.0%

360554

Sigma-Aldrich

Nitromethane, ACS reagent, ≥95%

270423

Sigma-Aldrich

Nitromethane, suitable for HPLC, ≥96%

690481

Sigma-Aldrich

N-[3,5-Bis(trifluoromethyl)phenyl]-N′-[(8a,9S)-6′-methoxy-9-cinchonanyl]thiourea, 90%

73478

Sigma-Aldrich

Nitromethane, puriss., absolute, over molecular sieve, ≥98.5% (GC)

690384

Sigma-Aldrich

N-[3,5-Bis(trifluoromethyl)phenyl]-N′-[(8a,9S)-10,11-dihydro-6′-methoxy-9-cinchonanyl]thiourea, 90%