In September 2015, world leaders gathered in New York to endorse the Sustainable Development Goals (SDGs): Ban Ki-moon asserts that the SDGs signal a 'paradigm shift for people and the planet' (UN 2014: para. 24). Significantly, under this new agenda there are expectations that businesses, government and civil society actors will be equally responsible for progressing a more sustainable path forward. Many assert that the private sector has particular strengths to bring to bear in delivering on the SDGs, including innovation, responsiveness, efficiency and provision of specific skills and resources. Interestingly, the business sector had a strong role in influencing development of the SDGs. In this paper we discuss the challenge being put forth to business actors by the SDGs, reflecting on both the potential for more sustainable and responsible practices and on the limits to change.
The known relationships between the mechanism of aliphatic substitution and the structures of the compounds substituted form a starting point for the investigation of the laws governing the steric orientation of substitution. As a result of work reported in the preceding papers, certain general principles relating to the orientation of substitution are advanced. Detailed discussion is confined to the reciprocal replacements of *Hal and -OR, and within this field previously recorded stereochemical observations are to a large extent rationalised. A fuller statement of the conclusions is given on p. 1270.NOTWITHSTANDING the large number of investigations that have been carried out since Walden's discovery of the inversion known by his name, much uncertainty still attaches to the rules and conditions that control the steric course of substitution a t a saturated carbon atom. This is due partly to the difficulty of relating sign of rotation to molecular configuration. But a still more important cause is that the conditions controlling steric orientation are intimately dependent on the mechanism of substitution, and it is only within comparatively recent years that mechanism in aliphatic substitution has been fruitfully studied. In this field, mechanism has been elucidated principally through the examination of reaction kinetics, by means of which an intelligible relationship has been traced between mechanism, on the one hand, and the chemical structures of reactants, and the physical conditions of reaction, on the other. I t was an obvious sequel to apply kinetics in order to elucidate the factors controlling the steric course of substitution ; and the procedure has two advantages. First, we can often decide the steric orientation of a reaction by comparison on the basis of mechanism (which kinetic results help to establish) with some other reaction whose steric course is known. Secondly, it should be possible to establish an empirical connexion between steric orientation and kinetics; and thus, using our present knowledge of the relation of kinetics to mechanism, to link steric orientation with mechanism and its determining factors, chemical structure and physical conditions. We have therefore studied the bptical effect of substitution a t an asymmetric carbon atom under conditions, not chosen haphazard, but defined by parallel studies of kinetics. I t is our view that much of the previous work on the Walden inversion requires repetition with this form of control (cf. Cowdrey, Hughes, and Ingold, Nature, 1936, 138, 759).In the present paper we set forth conclusions based largely on the experimental studies recorded in the previous five papers. We deal here only with the reciprocal replacements of -Hal and *OR, and this only in a preliminary way : extensions of the study in this field, and likewise our investigations on the substitutions which involve *NR,, will be described in future groups of papers.On the theoretical side our starting point is the general survey given by Hughes and Ingold (J., 1935, 244) of aliphat...
The plan underlying the investigation as developed in this collection of papers, which includes papers of several concurrent series, is explained. The series to which this paper belongs is concerned with the kinetics and products of aromatic nitration. The other series deal with various kinds of physical and synthetical evidence, all bearing directly or indirectly on the subject of nitration. In this paper the kinetics of aromatic nitration by nitric acid are considered. The treatment is divided into Sections, and the following summary of the paper is intended to render any of its Sections intelligible without the necessity of reading the others.(1) Kinetic Orders of Aromatic Nitration : The Nitronium Ion (p. 2402).-Aromatic nitration displays second-order kinetics in sulphuric acid (Martinsen), and first-order kinetics in nitric acid ; and in either nitromethane or acetic acid with nitric acid in constant excess, it exhibits zeroth-order kinetics for sufficiently reactive aromatic compounds, and first-order kinetics for sufficiently unreactive compounds. Nothing of special interest concerning mechanism follows from these kinetic results in sulphuric acid, and in nitric acid, though they are consistent with what is deduced; but the zeroth-order kinetics in organic solvents, and its transition to firstorder kinetics with diminishing aromatic reactivity, proves without alternative the formation and effectiveness of the nitronium ion, NO,+. The kinetically fundamental process is shown to be localised in nitric acid, t o be activated, to be heterolytic, and to produce electron-deficient nitrogen. Therefore it is the bond-fission HO-;NO, + HO-+KO,+ I disregarding the associated, instantaneous proton-transfers, which are treated under (2).(2) Solute Effects on Nitration Kinetics : Mechanism of Formation of the Nitronium Ion (p. 2412) .-Aromatic nitration in nitric acid, or in nitromethane, or acetic acid, with nitric acid in constant excess, is accelerated by sulphuric acid, and retarded by ionising nitrates, the latter effect being specific, and not a general salt effect. The effect of sulphuric acid on the rate, and that of nitrate ion on the reciprocal of the rate, obey linear limiting laws. The effects occur alike with zeroth-and first-order reactions, always without disturbance to the reaction order.These results show that one proton is employed, and one nitrate ion eliminated, in the conversion of nitric acid into a nitronium ion; and that these changes are reversed. It also follows that they take place in an earlier reaction-step than that which produces nitronium ion, because a zeroth-order nitration only maintains its kinetic order when the latter step is not reversed. Thus the following two-stage mechanism is unequivocally established : 2HK0, H,N03+ + NO3-(fast) H,N03+ + NO,+ + H,O (slow)Consistently, the kinetic effect of water in zeroth-order nitration is negligible in comparison with that of nitrate ion. Relatively large amounts of water will retard the nitration by reversing the second of the above reacti...
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