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A combination of Ga(I) centers as important building blocks and scaffolds containing N-heterocyclic imines gives new insights into low-valent Ga chemistry. In this study, a mixture of LDipNLi (LDip = 1,3-bis(2,6-diisopropylphenyl)-imidazolin-2-ylidene), tBuOK, and Cp*Ga (Cp* = pentamethylcyclopentadienyl) in toluene afforded [LDipN-Ga]2 (1) via salt metathesis. X-ray structure analysis of 1 revealed a four-membered Ga2N2 ring, and DFT studies indicated the presence of a lone pair at each Ga center. In addition, compound 1 demonstrated diverse reactivities towards methyl trifluoromethanesulfonate, diphenyl disulfide, 9,10-phenanthrenequinone, and ECl2 (E = Ge or Sn). [ABSTRACT FROM AUTHOR]

C9H7F3I3NO, monoclinic, P21/n (no. 14), a = 7.5581(4) Å, b = 20.9303(11) Å, c = 9.3548(5) Å, β = 92.208(5)°, V = 1478.78(13) Å3, Z = 4, Rgt(F) = 0.0336, wRref(F2) = 0.0610, T = 290 K.

α-Phenylglyoxylic acid is a novel cyclization reagent. In this study, three cyclization products were synthesized by the reaction of α-phenylglyoxylic acids with ortho -functionalized anilines in deep eutectic solvents (DES). The five-membered-ring-formation products, the 2-arylbenzothiazoles, with a highest yield of 88%, were obtained by the reaction between 0.30 mmol of an o -aminothiophenol and 0.30 mmol of an α-phenylglyoxylic acid in choline chloride (ChCl)/ d -(–)-tartaric acid DES at 60 °C for 0.5 h. The six-membered-ring-formation products, 3-aryl-2 H -benzo[ b ][1,4]oxazin-2-one derivatives, were obtained in yields up to 99% by the reaction between 0.30 mmol of an o -aminophenol and 0.60 mmol of an α-phenylglyoxylic acid in ChCl/urea DES at 80 °C for 2.0 h. In the reaction between 0.30 mmol of o -phenylenediamine and 0.45 mmol of an α-phenylglyoxylic acid in ChCl/anhydrous tin(II) chloride DES at 70 °C for 1.5 h, the six-membered-ring-formation products, 3-arylquinoxalin-2(1 H)-one derivatives, were synthesized, with a highest yield of 96%. This cyclization reaction occurred without the addition of other catalysts, and the title compounds were obtained with good yields under mild conditions. [ABSTRACT FROM AUTHOR]

4 H -Pyrano[3,2- c ]coumarin derivatives are an important class of pharmaceutical compounds that are expensive to prepare by previously reported methods. An efficient and green method was developed to obtain these derivatives using the deep eutectic solvent (DES) zinc chloride/acetamide (n:n = 1:4), which acted as both the catalyst and the solvent for the reaction. An aromatic aldehyde, 4-hydroxycoumarin, and cyanoacetate were used as the substrates. The DES, substrate molar ratio, diluent type, temperature, and reaction time were optimized to obtain the 4 H -pyrano[3,2- c ]coumarin derivatives from a range of aromatic aldehydes in a single step in moderate to high yields and under mild reaction conditions. [ABSTRACT FROM AUTHOR]

This is the first report of a simple and general method for acetalization- of aldehydes via an α-chymotrypsin-induced reaction under mild conditions. A broad range of aromatic and heteroaromatic aldehydes have been acetalized under neutral conditions in good yields using a catalytic amount of chymotrypsin. [ABSTRACT FROM AUTHOR]

The ovules or seeds (fertilized ovules) with wings are widespread and especially important for wind dispersal. However, the earliest ovules in the Famennian of the Late Devonian are rarely known about the dispersal syndrome and usually surrounded by a cupule. From Xinhang, Anhui, China, we now report a new taxon of Famennian ovules, Alasemenia tria gen. et sp. nov. Each ovule of this taxon possesses three integumentary wings evidently extending outwards, folding inwards along abaxial side and enclosing most part of nucellus. The ovule is borne terminally on smooth dichotomous branches and lacks a cupule. Alasemenia suggests that the integuments of the earliest ovules without a cupule evolved functions in probable photosynthetic nutrition and wind dispersal. It indicates that the seed wing originated earlier than other wind dispersal mechanisms such as seed plume and pappus, and that three- or four-winged seeds were followed by seeds with less wings. Mathematical analysis shows that three-winged seeds are more adapted to wind dispersal than seeds with one, two or four wings under the same condition., Competing Interests: DW, JY, LL, YZ, PX, MQ, PH No competing interests declared, (© 2024, Wang, Yang, Liu et al.)

A combination of Ga(I) centers as important building blocks and scaffolds containing N-heterocyclic imines gives new insights into low-valent Ga chemistry. In this study, a mixture of L Dip NLi (L Dip = 1,3-bis(2,6-diisopropylphenyl)-imidazolin-2-ylidene), t BuOK, and Cp*Ga (Cp* = pentamethylcyclopentadienyl) in toluene afforded [L Dip N-Ga] 2 (1) via salt metathesis. X-ray structure analysis of 1 revealed a four-membered Ga 2 N 2 ring, and DFT studies indicated the presence of a lone pair at each Ga center. In addition, compound 1 demonstrated diverse reactivities towards methyl trifluoromethanesulfonate, diphenyl disulfide, 9,10-phenanthrenequinone, and ECl 2 (E = Ge or Sn).