Organic Chemistry of Explosives

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Synthetic Routes to Aliphatic

C-Nitro Functionality

1.1 Introduction

The nitro group, whether attached to aromatic or aliphatic carbon, is probably the most widely

studied of the functional groups and this is in part attributed to its use as an ‘explosophore’ in

many energetic materials.^1 The chemistry of the nitro group has been extensively reviewed in

several excellent works including in a functional group series.^2 –^8

A comprehensive discussion of the synthetic methods used to introduce the nitro group into

aliphatic compounds, and its diverse chemistry, would require more space than available in this

book. While every effort has been made to achieve this, some of these methods are given only

brief discussion because they have not as yet found use for the synthesis of energetic materials,

or their use is limited in this respect. The nature of energetic materials means that methods

used to introduce polynitro functionality are of prime importance and so these are discussed

in detail. Therefore, this work complements the last major review on this subject.^9

The chemical properties of the nitro group have important implications for the synthesis of

more complex and useful polynitroaliphatic compounds and so these issues are discussed in

relation to energetic materials synthesis.

RCH 2 NO 2

Primary nitroalkane

R^1 R^2 CHNO 2

Secondary nitroalkane

R^1 R^2 R^3 CNO 2

Tertiary nitroalkane

RCH(NO 2 ) 2

Terminal gem-dinitroalkane

R^1 R^2 C(NO 2 ) 2

Internal gem-dinitroalkane

R^1 R^2 CHC(NO 2 ) 3

Trinitromethyl

Figure 1.1

Aliphatic nitroalkanes can be categorized into six basic groups: primary, secondary and

tertiary nitroalkanes, terminal and internalgem-dinitroalkanes, and trinitromethyl compounds.

Primary and secondary nitroalkanes, and terminalgem-dinitroalkanes, have acidic protons

and find particular use in condensation reactions for the synthesis of more complex and

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