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The reactions named in the title, which form the respective 2,4-dinitro-l-naphthylbutylamines (8), occur in two distinct stages. The spectrum of an intermediate develops at a rate which is measurable in a stopped-flow apparatus, and then decays at a slower and easily measurable rate. The kinetics of both stage I and stage II have been studied, and equilibrium constants have been determined for the stage I equilibrium and the acid-base equilibrium between product 8 and its conjugate base 9. The evidence indicates that the observable intermediate is the conjugate base (7) of the initial complex (6). Formation of the intermediate is not base catalyzed. Its transformation to product 8 is first order in butylammonium ion but independent of amine concentration. The mechanism of base catalysis of the overall reaction is thereby indicated to be general acid catalysis of leaving group expulsion from the conjugate base of the -complex intermediate.

Both of the title systems undergo rapid halogen exchange (half-life ca. 1−2 min) in N-methylpyrolidinone with catalytic sodium hydroxide at room temperature. Yet they differ markedly in response to added p-dinitrobenzene. The rate of the haloform exchange is unaffected, whereas the rate of the carbon tetrahalide exchange is severely retarded. The known base-induced halogen exchange reaction between chloroform and bromoform is shown not to proceed through a reversible carbene intermediate as claimed in the literature. It appears to be best described in terms of the so-called RARP mechanism (radical anion−radical pair). The mechanism proposed for the rapid exchange between carbon tetrachloride and carbon tetrabromide is initial electron transfer, halide ion loss, and ensuing radical chain scrambling of halogen atoms. The acronym RARC, standing for radical anion−radical chain, is proposed.

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Two concise syntheses of the experimental rice herbicide 2,2dimethyl-1-(4-methylthio-5-pyrimidinyl)indane are reported. The initial synthesis relies on a low-temperature addition of 5-lithio-4-methylthiopyrimidine to 2,2-dimethyl-1-indanone to construct the pyrimidinylindane system. Process improvements to this route are described and resulted in the preparation of 90 kg of the title compound on pilot plant scale. Economics dictated the need to identify a new synthetic route which utilized inexpensive raw materials. Detailed herein is the initial discovery of a new route which features a novel combination of dissolving metal reduction/formylation/cyclization to construct the requisite pyrimidine ring. Process improvements to this chemistry have allowed us to deliver an appropriately substituted pyrimidinylindane in a minimal number of synthetic operations.