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Cinnamic acids have been prepared in moderate to high yields by a new direct synthesis using aromatic aldehydes and aliphatic carboxylic acids, in the presence of boron tribromide as reagent, 4-dimethylaminopyridine (4-DMAP) and pyridine (Py) as bases and N-methyl-2-pyrolidinone (NMP) as solvent, at reflux (180-190°C) for 8-12 hours.

Purpose-The purpose of this paper is to describe a real-world system developed for a large food distribution company which requires forecasting demand for thousands of products across multiple warehouses. The number of different time series that the system must model and predict is on the order of 10 5. The study details the system's forecasting algorithm which efficiently handles several difficult requirements including the prediction of multiple time series, the need for a continuously self-updating model, and the desire to automatically identify and analyze various time series characteristics such as seasonal spikes and unprecedented events. Design/methodology/approach-The forecasting algorithm makes use of a hybrid model consisting of both statistical and heuristic techniques to fulfill these requirements and to satisfy a variety of business constraints/rules related to over-and under-stocking. Findings-The robustness of the system has been proven by its heavy and sustained use since being adopted in November 2009 by a company that serves 91 percent of the combined populations of Australia and New Zealand. Originality/value-This paper provides a case study of a real-world system that employs a novel hybrid model to forecast multiple time series in a non-static environment. The value of the model lies in its ability to accurately capture and forecast a very large and constantly changing portfolio of time series efficiently and without human intervention.

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Polyimides containing 1,4-dithiine units and corresponding thiophene units were synthesized by the nucleophilic substitution reaction of bis(dichloro-maleimide) arylene derivatives with sodium sulfide. Their structures were confirmed by IR and UV spectroscopy and elemental analysis. The polymers were characterized by viscosimetric measurements, softening points and thermogravimetric data.

New poly[N-(ester)-3-(ether)-4-(chloro)]maleimides were synthesized by the reaction of N-(4-chlorocarbonylphenyl)-3,4-dichloromaleimide (3) with various bisphenols such as hydroquinone (8a), 2,2-bis-(4-hydroxypheny1)propane (8b), 4,4'-(hexafluoroisopropy1idene)diphenol (8c), and 2,5-bis(4-hydroxybenzylidene)cyclopentanone (8d). The structures of the resulted polymers were confirmed by IR and elemental analyses. A series of model compounds (4-7) was synthesized to facilitate confirmation of the structure of the polymers. The polymer containing hydroquinone units (9a) exhibited LC behavior in the melt, as observed by PLM measurements.

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