The NEF Reaction

Wayland E. Noland

doi:10.1021/cr50001a003

ChemInform Abstract: Concave Reagents. Part 4. Protonation of Nitronate Anions via Concave Pyridines. Stereoselective C-Protonation versus Nef Reaction.

ChemInform ◽

10.1002/chin.199015072 ◽

1990 ◽

Vol 21 (15) ◽

Author(s):

U. LUENING ◽

R. BAUMSTARK ◽

M. MUELLER ◽

C. WANGNICK ◽

F. SCHILLINGER

Keyword(s):

Nef Reaction ◽

Concave Reagents

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A Synthesis of 2-Amino-2,6-dideoxy-D-(and L-)galaetose (Fucosamine) and 2-Amino-2,6-dideoxy-D-(and L-)talose (Pneumosamine)

Canadian Journal of Chemistry ◽

10.1139/v73-143 ◽

1973 ◽

Vol 51 (6) ◽

pp. 974-977 ◽

Cited By ~ 21

Author(s):

Malcolm B. Perry ◽

Virginia Daoust

Keyword(s):

Similar Reaction ◽

Reaction Sequence ◽

Reaction Conditions ◽

Nef Reaction ◽

Methanolic Ammonia

5-Deoxy-D-lyxose underwent base-catalyzed addition with nitromethane to give a mixture of 1,6-dideoxy-1-nitro-D-galactitol and 1,6-dideoxy-1-nitro-D-talitol (ca. 2:1). Acetylation of the crystalline 1,6-dideoxy-1-nitro-D-galactitol gave 2,3,4,5-tetra-O-acetyl-1,6-dideoxy-1-nitro-D-galactitol which on treatment with methanolic ammonia afforded 2-acetamido-1,2,6-trideoxy-1-nitro-D-talitol and 2-acetamido-1,2,6-trideoxy-1-nitro-D-galactitol (ca. 3:1) which under the modified Nef reaction conditions gave 2-acetamido-2,6-dideoxy-D-talose and 2-acetamido-2,6-dideoxy-D-galactose respectively. The glycoses were converted to 2-amino-2,6-dideoxy-D-talose hydrochloride and 2-amino-2,6-dideoxy-D-galactose hydrochloride on hydrolysis with hydrochloric acid.A similar reaction sequence applied to 5-deoxy-L-lyxose afforded the L-enantiomorphic intermediates, and gave 2-amino-2,6-dideoxy-L-talose hydrochloride and 2-amino-2,6-dideoxy-L-galactose hydrochloride as final products.

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Cathodic hydrodimerization of nitroolefins

Beilstein Journal of Organic Chemistry ◽

10.3762/bjoc.11.131 ◽

2015 ◽

Vol 11 ◽

pp. 1163-1174 ◽

Cited By ~ 4

Author(s):

Michael Weßling ◽

Hans J Schäfer

Keyword(s):

Double Bond ◽

Nitro Group ◽

Bond Formation ◽

Cathodic Reduction ◽

High Yield ◽

Easy Access ◽

Electrolysis Cell ◽

Aldehydes And Ketones ◽

Nef Reaction

Nitroalkenes are easily accessible in high variety by condensation of aldehydes with aliphatic nitroalkanes. They belong to the group of activated alkenes that can be hydrodimerized by cathodic reduction. There are many olefins with different electron withdrawing groups used for cathodic hydrodimerization, but not much is known about the behaviour of the nitro group. Synthetic applications of this group could profit from the easy access to nitroolefins in large variety, the C–C bond formation with the introduction of two nitro groups in a 1,4-distance and the conversions of the nitro group by reduction to oximes and amines, the conversion into aldehydes and ketones via the Nef reaction and base catalyzed condensations at the acidic CH bond. Eight 1-aryl-2-nitro-1-propenes have been electrolyzed in an undivided electrolysis cell to afford 2,5-dinitro-3,4-diaryl hexanes in high yield. The 4-methoxy-, 4-trifluoromethyl-, 2-chloro- and 2,6-difluorophenyl group and furthermore the 2-furyl and 2-pyrrolyl group have been applied. The reaction is chemoselective as only the double bond but not the nitro group undergoes reaction, is regioselective as a ß,ß-coupling with regard to the nitro group and forms preferentially two out of six possible diastereomers as major products.

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