ChemInform Abstract: SYNTH. VON VORSTUFEN DES LYSINS AUS 1‐NITRO‐BUTENYL‐NITRATEN

Abstract

Das bei der Nitrierung von Butadien‐(1,3) mit N2O5 in Methylenchlorid bei ‐40 bis ‐30°C entstehende Gemisch (Ausbeute 85%) der Nitrobutenylnitrate (I) und (II) läßt sich mit Nitroessigsäureäthylester bzw. Nitromalonsäuredi‐ äthylester in Gegenwart von Triäthylamin zu den Dinitroalkensäureestern (IVa) (25%) und (IVb) (45%) umsetzen.

Conjugated Nitrodienes. Synthesis and Reactivity

“…Although methods for the preparation of 1-nitroalkenes have been known for a long time, this is not the case for 1-nitro-1,3-dienes. As pointed out by Bloom et al , (see the Introduction), procedures for the preparation of these compounds were inefficient and their chemistry was scarcely investigated. ,− Furthermore, several of the 1-nitro-1,3-dienes described proved to be unstable under normal conditions. Thus, 1-nitrobuta-1,3-diene ,,, ( 90 ) (Figure ) quickly decomposes at room temperature, , being stable for only one week at −20 °C.…”

“…Heterocycloaddition between several 2-nitrodienes, either stable or unstable, and enol ethers gave adducts which, by acid hydrolysis, led to unsaturated 1,4-dicarbonyl compounds. 2 Scheme 9 illustrates this process for the synthesis of 31 (30% overall yield) from 2-nitrocyclohepta-1,3-diene (27) through nitronic ester 30.…”

“…Bloom et al , have reported that some of the methods described in the earlier Russian literature, mainly those concerning the synthesis of 1-nitro-1,3-dienes, − were inefficient, either because of their low yields or because the stereochemistry around the double bonds was unspecified. Furthermore, the products were obtained as mixtures, and competitive 1,4-additions were observed during their preparation.…”

Nitro-functionalized analogues of 1,3-Butadiene: An overview of characteristic, synthesis, chemical transformations and biological activity

“…Another alternative two-stepped process was described by Petrov et al 38,44 as well as Sulimov et al 45 (Scheme 3). For this option, in a first stage 1,3-butadiene (1) is converted to 1-iodo-4-nitrobut-2-ene (4) using nitrogen dioxide and iodine.…”

“…Next stage includes the dehydrohalogenation reaction of compound 4 with simultaneous reorganization of the molecule. The reaction can be carried under the action of lead acetate in glacial acetic acid 38,44 or, optionally, by using triethylamine in diethyl ether at -30 o C. 45 In order to prevent polymerisation of the nitrodiene Ia-1-trans hydroquinone was added to the reaction mixture. 45 Scheme 3.…”