Nitro-hexenes

Nitro-l-hexene (called 2-Nitro-hexen(l) in Ger), H2C C(N02)C4H9 liq, bp 81-2°at 50mm... 

Ar-[( )-4-ethyl-2-[(Z)-hydroxyimino]-5-nitro-hexen-1 -yl]3-pyridine carboxamide (NOR4) 48... 

Sequential radical cyclizations are also featured in an efficient and clever synthesis of the cedrane framework 83 (see Scheme 15).30 Compound 81, the product of a regioselective Diels-Alder reaction between isoprene (79) and nitroethylene (80), participates in a nitroaldol reaction (Henry reaction) with 5-methyl-4-hexenal in the presence of a basic resin to give 82. Because the nitro group in... 

A similar study has been reported using l-nitro-2-[(S,S)-2-phenylpropylsulfinyl]-l-cyclo-hexene and zinc enolates of tetrahydro-2(3//)-pyridinones34. 

A simple synthesis of allethrolone, the alcohol component of the allethrine (commercially important insecticide), is shown in Scheme 4.11. The conjugated addition of 3-phenylthio-5-hexene-2-one to 1-nitro-l-propene followed by the Nef reaction and aldol condensation gives allethrolone in good yield.68... 

Alternatively, Ballini devised a new strategy to synthesize tri-alkylated pyrroles from 2,5-dialkylfurans and nitroalkanes <00SL391>. This method involves initial oxidation of 2,5-dimethylfuran with magnesium monoperoxyphthalate to cA-3-hexen-2,5-dione (6). Conjugate addition of the nitronate anion derived from the nitro compound 7 to 6 followed by chemoselective hydrogenation of the C-C double bond of the resulting enones 8 (obtained by elimination of nitrous acid from the Michael adduct) completes the conversion to the alkylated y-diketones 9. Final cyclization to pyrroles 10 featured improved Paal-Knorr reaction conditions involving reaction of the diketones with primary amines in a bed of basic alumina in the absence of solvent. 

Under basic conditions, a-nitroalkenes function as synthetic equivalents of allylic nitro compounds 3-nitro-3-hexene, for instance, reacts with piperidine in the presence of Pd(PPh3)4, to give 2-piperidinyl-3-hexene (equation 139)459. 

The reaction of alkynes with dinitrogen tetroxide is less synthetically useful as a route to nitro compounds. The reaction of 3-hexyne with dinitrogen tetroxide yields a mixture of cis- and fran -3,4-dinitro-3-hexene (4.5% and 13% respectively), 4,4-dinitro-3-hexanone (8%), 3,4-hexanedione (16%) and propanoic acid (6%). 2-Butyne forms a mixture containing both cis- and fran -2,3-dinitro-2-butene (7 % and 34 % respectively). " ... 

CH2)a- 1,10/1,25 5-Jtid-6-nitro-1 -hexen 99,5 2,5-Dijod-l,6-dinitro- kexan <0,5... 

Hydroxy-5-nitro-bicyclo[3.3.0]oct-2-ene bzw. 9-Hydroxy-l-nitro-bicyclo [4.3.0]non-7-ene sind durch Umsetzung von 1-Nitro-cyclopenten brw. 1-Nitro-cyclo-hexen mit 2-Morpholino-3-oxo-l-buten zuganglich. 

Fishbein J.A.Gallaghan, JACS 76, 3218 (1954) CA 49,8991(1955)(P epn props of 2-amino- 1-nitro-1( 3-diazacyclo- 2-hexene 2-amino- 1-nitro- 1,3-diazacyclo- 2-hexene nitrate 2-amino-lil3-dinitrocyclo-2-hexanone and other derivs)... 

This second approach70 was based on the nitromethane synthesis,71 and involved, as the key intermediate, l-C-nitro-l-hexene-D-n6o-3,4,5,6-tetrol tetraacetate (66), previously reported by Sowden and Fischer.77 In re-studying their conversion of D-ribose (64) into the hexenetetrol (66), it was possible70 to secure 2,3,4,5,6-penta-O-acetyl-l-deoxy-l-nitro-D- altritol (65) as crystalline material. When (65) was subjected to the Schmidt-... 

Hexane 2-Fluor-l-nitro- ElOa, 129 (En 4 HFIHNO,). 627 (En 4 O,N[BF4Je) ElOb,. 348 (E11 + HF 0,N ) E16d. 163 (1-Hexen 4 02N[BF4)e) Pentanoic Acid 2-Ammo-3-fltioro-4-methyl- ElOa. 150 (SH -> F) EfiH,2F2 Butane... 

In order to probe this phenomenon quantitatively in an uncharged system where solvation effects are known to be relatively unimportant, the rates of cycloadditions of two relatively electron-deficient 1,3-dipoles, p-methoxy and p-nitro benzonitrile oxides (MBNO and NMBO, respectively) to a series of simple alkenes — propene, 1-butene, 1-pentene, 1-hexene, 3-methyl-l-butene, 3,3-dimethyl-l-butene and isobutene — were measured70. In each of these reactions, only the 5-alkyl-3-aryliso-xazolines were formed. 

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