Synthesis and Optical Properties of Cinnamylidene Derivatives of Malononitrile Trimer

Fluctuation spectroscopy of surface melting of ice with and without impurities

“…It should be noted that previous literature with thinner LLL, both theoretical and experimental [6,9,13,21], deal with ice in pure water vapor, without air, unlike our results, which might be the reason for the difference. For thin layers, viscosity might be larger than its value in bulk, though whether it is, and by how much if so, is an unsettled question [2,[49][50][51]. Since the surface thermal fluctuation spectrum behaves as ∼ h 3 /(ηf 2 ) for thin LLL, larger viscosities lead to larger h values in our results (Fig.…”

Synthesis and Solid State Fluorescence of Malononitrile Trimer Ylidene Derivatives in Aqueous Medium under Ultrasonication

“…Yield 85%, mp 292-293°C (decomp. ); published data [10]: mp 291-292°C (decop.). IR spectrum, ν, cm -1 : 2193 (C≡N); 1601 (C=C).…”

“…Compounds containing a 1,1,3,3-tetracyano propenide fragment have attracted much interest due to their great potential for the synthesis of five-and sixmembered heterocycles, including fused ones [1][2][3][4][5], as well as their thermo-and photochromic [6], semiconducting [7], magnetic [6,8], and chemosensory properties [9]. We previously reported the synthesis of potassium (Z)-4-aryl-2-(dicyanomethylidene)-1,1,3-tricyanobut-3-en-1-ides 1 and (3Z,5E)-6-aryl-2-(dicyanomethylidene)-1,1,3-tricyanohexa-3,5-dien-1-ides 2 by Knoevenagel condensation of substituted benzaldehydes [9] and cinnamaldehydes [10] with malononitrile trimer potassium salt 3 in propan-2-ol or in aqueous medium in the presence of surfactants, e.g., Oksipav AP [11]. Study of the optical properties of compounds 1 and 2 showed that they did not fluoresce in solution, except for derivatives containing a dimethylamino group in the benzene ring [10,11].…”

“…We previously reported the synthesis of potassium (Z)-4-aryl-2-(dicyanomethylidene)-1,1,3-tricyanobut-3-en-1-ides 1 and (3Z,5E)-6-aryl-2-(dicyanomethylidene)-1,1,3-tricyanohexa-3,5-dien-1-ides 2 by Knoevenagel condensation of substituted benzaldehydes [9] and cinnamaldehydes [10] with malononitrile trimer potassium salt 3 in propan-2-ol or in aqueous medium in the presence of surfactants, e.g., Oksipav AP [11]. Study of the optical properties of compounds 1 and 2 showed that they did not fluoresce in solution, except for derivatives containing a dimethylamino group in the benzene ring [10,11]. Herein, we describe a procedure for the synthesis of compounds 1 and 2 in aqueous medium under ultrasonic irradiation and their solid state fluorescence properties.…”