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1995 stereochemistry stereochemistry (general, optical resolution) O 0030 08 -073 Enantioselective Addition of Diethylzinc to α-Branched Aldehydes. -Among several tested catalysts cat.* gives the best asymmetric inductions. Good results are only obtained if the aldheyde has no . alpha.-hydrogen. -

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The real estate auction market has become increasingly important in the financial, economic and investment fields, but few artificial intelligence-based studies have attempted to forecast the auction prices of real estate. The purpose of this study is to develop forecasting models of real estate auction prices using artificial intelligence and statistical methodologies. The forecasting models are developed through a regression model, an artificial neural network and a genetic algorithm. For empirical analysis, we use Seoul apartment auction data from 2013 to 2017 to predict the auction prices and compare the forecasting accuracy of the models. The genetic algorithm model has the best performance, and effective regional segmentation based on the auction appraisal price improves the predictive accuracy.

We introduce ConnotationWordNet, a connotation lexicon over the network of words in conjunction with senses. We formulate the lexicon induction problem as collective inference over pairwise-Markov Random Fields, and present a loopy belief propagation algorithm for inference. The key aspect of our method is that it is the first unified approach that assigns the polarity of both word-and sense-level connotations, exploiting the innate bipartite graph structure encoded in WordNet. We present comprehensive evaluation to demonstrate the quality and utility of the resulting lexicon in comparison to existing connotation and sentiment lexicons.

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The generation of patterned images in polymer films has been extensively studied and used in fundamental and applied research areas. The development of patterned color or fluorescent images, especially, is of great technological importance in the electronics industry. Recently, the generation of functional images by selective immobilization of organic dyes in the polymer film has been reported. [1±3] Selective removal of acid-labile protecting groups through photoinduced chemical transformation followed by chemisorption of organic dyes from solution into the patterned polymer film has given micrometer-scale functional images. The two-step procedures described in the literature, however, have potential problems such as difficulty of dye penetration into polymer matrices and concern about longterm stability of the patterned images.To avoid these limitations, we have tried to develop a direct method of generating fluorescence images with a precursor molecule. The strategic basis for designing a precursor is that the precursor molecule is non-fluorescent and/or colorless, but becomes fluorescent and/or reveals color by photoinduced chemical changes. We have previously reported that the UV absorption maximum and fluorescence of quinizarin 1 can be readily altered and manipulated simply by blocking the intramolecular hydrogen bonds. [4] Thus, the UV absorption maximum (479 nm) of quinizarin 1 shifts to a shorter wavelength (335 nm) on blocking the two phenols with two tert-butoxycarbonyl (t-BOC) groups. In addition, the t-BOC-protected quinizarin 2 has virtually no fluorescence, whereas quinizarin 1 is strongly fluorescent due to the quasi-aromatic structure caused by intramolecular hydrogen bonding. As a part of our continuing interest in the generation of relief and functional images with transiently protected precursor molecules in polymer films, we now report the synthesis of a novel polymer having t-BOC-protected quinizarin moieties and the genera-tion of color and fluorescent images by photolithographic methods. To our knowledge, this is the first example of finely resolved fluorescent images with a polymer having transiently protected precursor pendants.The strategies employed for the synthesis of t-BOC-protected quinizarin monomer 7 are shown in Scheme 1. Aldol condensation of leucoquinizarin (3) with 5-(benzyloxy)pentanal (4) [5] in the presence of piperidinium acetate in 2-propanol under Marschalk conditions [6] readily afforded the key intermediate, 2-substituted quinizarin 5, in an excellent yield (96 %). The intermediate 5, obtained as a pale red solid, has strong fluorescence due to intramolecular hydrogen bonding, confirming the proposed structure. Protection of the two phenol groups of 5 with di-tert-butyl dicarbonate in the presence of a catalytic amount of 4-dimethylaminopyridine (DMAP) in tetrahydrofuran (THF) provided the t-BOC-protected 2-substituted quinizarin 6 in 92 % yield. The fluorescence is virtually eliminated in the t-BOC-protected intermediate 6 and the position of the UV absorp-[**] We...