Municipal engineering, at one time the career of choice for many civil engineers, has changed, as has the manner in which municipal works are now delivered. This paper looks at what the municipal engineer does, where the work is done and the skill sets required to perform the work. New skill sets, required for the future, are then examined against a background of changes in legislation together with environmental pressures affecting local authorities. The information has been examined to show what the skill sets of the engineer of the future might be and how the municipal engineer might need to change in order to meet future challenges. Account is taken of the authors' experience in local government and private industry. Visits were made to seven local authorities in the north west of England and a staff questionnaire was conducted in the region in order that data could be gathered on the topic.
4-Diazoacetylthianthren with perchloric acid in acetonitrile gave 2-oxo-1,2-dihydrothieno[3,2,1 -de] -thianthrenium perchlorate which gave the corresponding enol ether with diazomethane. This ether was compared with 3-methoxy-1 -methylbenzo[b]thiophenium perchlorate, prepared from 3-methoxythiophen, and which was much more stable to solvolysis than the demethoxy-analogue. In contrast to the 4-diazoacetylthianthren, 7diazoacetyl-2-methylbenzo[b]thiophen with acetonitrile and perchloric acid cyclised in an alternative mode to give a new synthesis of 2-methyl-4-substituted oxazolium perchlorates.
Pyridinium methylides combine with hex-3-yne-2.5-dione. but-3-yn-2-one. methyl but-2-ynoate. methyl phenylacetylenecarboxylate, dimethyl penta-2.3-dienedioate, and ethyl 2-methylbuta-2.3-dienoate and 2-methylpenta-2.3-dienoate to give indolizines, identified from spectra.Road, Oxford OX1 3QU DIETHYL and dimethyl acetylenedicarboxylate 2 and the much less investigated propiolic esters3 give a wide variety of products with nitrogen-cont aining he t erocycles and y l i d e ~, ~ and the reactions of but-3-yn-2-one with some pyridine derivatives have been reportedS6 Few other activated acetylenes and allenes have been examined in this connection and the present paper described some initial investigations.Goldschmidt and Zoebelein have reported the oxidation of hex-3-yne-2,5-diol to the 5-hydroxy-2-one (45%) and the 2,5-dione (1) (10%) by chromium trioxide MeCO-C C-COMe 9 MeCO(ArNH1C =CH.COMe ArNHZ (1) (2) Ar =Ph (3) Ar = 4 -N 0 2 C 6 H ~in aqueous sulphuric acid,? but we found their procedure satisfactory only for preparing a mixture (n.m.r. analysis) of the hydroxy-ketone (65%) and the diketone ( l O ~o ) . The hydroxy-ketone was obtained pure (n.m.r.) by distillation in vacuo from sufficient 4-nitroaniline to convert the diketone into the nitroanilino-derivative (3). None of the diketone was obtained from further oxidation of the hydroxy-ketone under the conditions recommended.6 Only about half the oxidant had been consumed 4 h after its addition, but the amount of diketone isolable at this point or 20 h later was the same. The diketone was apparently oxidized to acetic acid at a rate comparable to that for its formation, and proved difficult to separate from unchanged hydroxy-ketone. Use of manganese dioxide as oxidant in an inert solvent 8 gave a maximum diketone : hydroxy-ketone ratio of 1 : 9 (n.m.r.), the diketone again being further oxidized. The least unsatisfactory but reproducible preparation of hex-3-yne-2,5-dione ( 10-18~o) was the oxidation with chromic acid of a mixture of the diol and the hydroxyketone.Hex-3-yne-2,5-dione is much more reactive than dimethyl acetylenedicarboxylate g towards aniline and 4-nitroaniline, for in methanol, which usually gives the
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.