ORGANIC SPECTROSCOPY INTERNATIONAL

ORGANIC SPECTROSCOPY INTERNATIONAL:



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Methyl 6-nitro-2-norbornene-5-carboxylate

Methyl (E)-3-nitroacrylate is a reactive dienophile in the Diels-Alder reaction. With cyclopentadiene it gives the corresponding adduct, methyl 6-nitro-2-norbornene-5-carboxylate, in 43% yield in refluxing benzene⁹ or in quantitive yield in ether at 0°,¹⁰ as shown below. The adduct was shown by NMR analysis to consist of an 86 : 14 mixture of endo- : exo-nitro stereoisomers, which could not be separated by crystallization.¹⁰

METHYL (E)-3-NITROACRYLATE

[2-Propenoic acid, 3-nitro-, methyl ester (E)-]

¹H NMR (60 MHz, CDCl₃): δ 3.8 (s, 3H, OCH₃), 6.95 (d, J = 14 hz, 1H, =CHNO₂-), 7.55 (d, J = 14 Hz, 1H, =CHNO₂): IR (CCl₄): cm.⁻¹ 3100 s, 3000 m, 2950 s, 2880 m (all CH), 1720 s (C=O), 1640 ms (C=C), 1530 s and 1350 s (NO₂).

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References 

1. N. F. Blom, D. M. F. Edwards, J. S. Field, and J. P. Michael, J. Chem. Soc. Chem. Commun., 1240 (1980).

Drug Patents International

Drug Patents International:



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Making Heterocycles Behave In C-H Activation

 

 

Yu and Dai’s C–H activation method overcomes traditional selectivity limitations, activating the C–H bond next door to a powerful directing group (red bonds).

Making Heterocycles Behave In C-H Activation

Organic Chemistry: Reaction overcomes traditional selectivity issues when applied to complex, druglike molecules.
read at
http://cen.acs.org/articles/92/i46/Making-Heterocycles-Behave-CH-Activation.html