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https://www.selleckchem.com/products/cx-5461.html We propose electrospray-ionization (ESI) mass spectrometry as a robust and powerful method for the in situ analysis of carbanions. ESI mass spectrometry selectively probes the charged components of the sampled solution and, thus, is ideally suited for the detection of free carbanions. We demonstrate the potential of this method by analyzing acetonitrile solutions of 15 different carbon acids AH, whose acidities cover a range of 11.1 ≤ pKa(DMSO) ≤ 29.5. After treatment with KOtBu as a strong base, all but the two least acidic compounds were successfully detected as free carbanions A- and/or as potassium-bound aggregates [Kn-1An]-. The association equilibria can be shifted toward smaller aggregates and free carbanions by the addition of the crown ether 18-crown-6, which facilitates the evaluation of the mass spectra. When KOtBu was replaced by other bases (LiOH, LiNiPr2, NaH, NaOH, KOH, NBu4OH) or when tetrahydrofuran or methanol was used as a solvent, carbanions were also successfully observed. For further demonstrating the utility of the proposed method, we applied it to the analysis of the Michael addition of deprotonated dimedone to butenone. ESI mass spectrometry allowed us to follow the decrease of the reactant carbanion and the buildup of the product carbanion in time.To date, most of the low-molecular-weight gels are found serendipitously, and modification on known gelator structures via organic synthesis is an efficient methodology to prepare gel series. However, a simple, direct, and rational modification method for a known gelator is still a challenge. Herein, we employ Glaser coupling reaction to synthesize a novel dendrimer gelator BisDEC with the (ALS2)2 structure, starting from terminal alkyne-based gelator DEC with the ALS2 structure. This structural change results in gels with distinct gelation solvents, mechanical properties, and stimuli-responsive abilities. The gelation abilities of DEC and BisDEC i

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