Development of a method for the synthesis of 2,4,5-trisubstituted oxazoles composed of carboxylic acid, amino acid, and boronic acid

• Kohei Yamada,
• Naoto Kamimura and
• Munetaka Kunishima

Beilstein J. Org. Chem. 2017, 13, 1478–1485, doi:10.3762/bjoc.13.146

• one-pot oxazole synthesis/Suzuki–Miyaura coupling sequence has been developed. One-pot formation of 5-(triazinyloxy)oxazoles using carboxylic acids, amino acids and a dehydrative condensing reagent, DMT-MM, followed by Ni-catalyzed Suzuki–Miyaura coupling with boronic acids provided the corresponding

• synthesis of oxazolone from carboxylic acids and amino acids using a dehydrative condensing reagent, 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium chloride (DMT-MM [19][20][21][22])[23]. Formation of 5-(triazinyloxy)oxazole is also reported to occur when an excess of DMT-MM was used. Recently

• carboxylic acid 1 and amino acid 2 under conditions improved from [23] (Table 1). A one-pot sequence involving formation of an activated ester from benzoic acid (1a) with DMT-MM, N-benzoylation of alanine (2a), cyclodehydration, and introduction of the triazinyl group was conducted in 1,4-dioxane/H2O to give

Strategies toward protecting group-free glycosylation through selective activation of the anomeric center

• A. Michael Downey and
• Michal Hocek

Beilstein J. Org. Chem. 2017, 13, 1239–1279, doi:10.3762/bjoc.13.123

• -(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-morpholinium chloride (DMT-MM). The isolated yields were moderate but the reaction was perfectly stereoselective for the 1,2-trans products (Scheme 32). The product was also formed when using water as the solvent. The DMT glycoside was subsequently treated with 10

Versatile synthesis of end-reactive polyrotaxanes applicable to fabrication of supramolecular biomaterials

• Atsushi Tamura,
• Asato Tonegawa,
• Yoshinori Arisaka and
• Nobuhiko Yui

Beilstein J. Org. Chem. 2016, 12, 2883–2892, doi:10.3762/bjoc.12.287

• (DMT-MM). However, the PRX peak is not detected, presumably because of the dethreading of α-CDs, even though the terminal groups of the axle polymer are capped with 2a. Therefore, 2a is insufficient bulky to prevent the dethreading of CDs from PRXs. To achieve the synthesis of end-reactive

• )ethylamine (HEEA) were obtained from TCI (Tokyo, Japan). 4-(4,6-Dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium chloride (DMT-MM) and copper(II) sulfate pentahydrate (CuSO4) were obtained from Wako Pure Chemical Industries (Osaka, Japan). N,N’-Carbonyldiimidazole (CDI) and (+)-sodium L-ascorbate were

• temperature. After the reaction, the precipitate was collected by centrifugation and freeze-dried for 1 day to obtain a pseudopolyrotaxane as powder (yield 1.37 g). Then, 4-(azidomethyl)benzoic acid (106 mg, 597 μmol), DMT-MM (165 mg, 597 μmol), and the pseudopolyrotaxane were allowed to react in methanol (14

Potent triazine-based dehydrocondensing reagents substituted by an amido group

• Munetaka Kunishima,
• Daiki Kato,
• Nobu Kimura,
• Masanori Kitamura,
• Kohei Yamada and
• Kazuhito Hioki

Beilstein J. Org. Chem. 2016, 12, 1897–1903, doi:10.3762/bjoc.12.179

• -substituted chlorotriazine is readily converted to a stable, non-hygroscopic triazinylammonium-based dehydrocondensing reagent that is superior to 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium chloride (DMT-MM) in terms of its reactivity in dehydrocondensing reactions. Keywords: amide-forming

• reagent, 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium chloride (DMT-MM) (Scheme 1a,b) [1][2][3][4][5]. The mechanism of the reaction shown in Scheme 1b involves the acyloxytriazine intermediate 4, which has appropriate reactivity and sufficient stability to hydrolysis or alcoholysis. This

• feature enables the use of DMT-MM for dehydrocondensing reactions in water or alcohols to give amides without the recovery of hydrolyzed carboxylic acids and the formation of corresponding esters. DMT-MM is quantitatively synthesized from 2-chloro-4,6-dimethoxy-1,3,5-triazine (CDMT) and N-methylmorpholine

New synthetic strategies for xanthene-dye-appended cyclodextrins

• Milo Malanga,
• Andras Darcsi,
• Mihaly Balint,
• Gabor Benkovics,
• Tamas Sohajda and
• Szabolcs Beni

Beilstein J. Org. Chem. 2016, 12, 537–548, doi:10.3762/bjoc.12.53

• can reversibly cyclize. In this context we report a green approach for the synthesis of switchable xanthene-dye-appended cyclodextrins based on the coupling agent 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium chloride (DMT-MM). By using 6-monoamino-β-cyclodextrin and commercially available

• supramolecular assembly of the xanthene-dye-appended cyclodextrins were developed based on the set of data collected by the extensive NMR characterization. Keywords: DMT-MM; fluorescein; rhodamine; supramolecular assembly; Introduction Cyclodextrins (CDs) are cyclic oligosaccharides consisting of 6, 7 or 8

• our knowledge, is always performed in organic solvent under harsh conditions [8]. The synthesis and the use of 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium chloride (DMT-MM) as a coupling agent for the formation of amides and esters was first reported by Kunishima et al. [9]. This

Supramolecular hydrogels formed from poly(viologen) cross-linked with cyclodextrin dimers and their physical properties

• Yoshinori Takashima,
• Yang Yuting,
• Miyuki Otsubo,
• Hiroyasu Yamaguchi and
• Akira Harada

Beilstein J. Org. Chem. 2012, 8, 1594–1600, doi:10.3762/bjoc.8.182

• using 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium chloride n-hydrate (DMT-MM) as a condensing reagent in DMF. The α,β-CD dimer is prepared by reacting 6-amino-α-CD and 6-O-(4-carboxylphenylamide)-β-CD using DMT-MM in DMF. These CD dimers are purified by preparative reversed-phase

• mmol) were dissolved in dried DMF (20 mL). DMT-MM (34 mg, 0.12 mmol) was added and the mixture was stirred at rt for 4 days. After evaporation of the solvent, the residue was dissolved in water (10 mL) and poured into acetone (100 mL). The product was collected and purified by reversed-phase

• –4.79 (m, 7H, C(1)H of β-CD), 4.45–4.32 (m, 6H, O(6)H of β-CD), 3.74–3.51 (m, C(3,6,5,3,4)H of α-CD); TLC: Rf 0.32 (n-butanol/ethanol/water 5:4:3). c) α,β-CD dimer The synthetic procedure was the same as α,α-CD dimer, using terephthalic acid-β-CD (65 mg, 50 μmol), 6-NH2-α-CD (59 mg, 60 μmol), DMT-MM

Symmetrical and unsymmetrical α,ω-nucleobase amide-conjugated systems

• Sławomir Boncel,
• Maciej Mączka,
• Krzysztof K. K. Koziol,
• Radosław Motyka and
• Krzysztof Z. Walczak

Beilstein J. Org. Chem. 2010, 6, No. 34, doi:10.3762/bjoc.6.34

• - and bis-amide conjugated systems containing aliphatic, aromatic or saccharidic linkages. The final stage of the synthesis involves condensation of a subunit bearing carboxylic group with an amine subunit. 4-(4,6-Dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium chloride (DMT-MM) was found to be a

• carboxylic subunit with an amino compound. As condensing agent, 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium chloride (DMT-MM) was found to be very convenient and efficient (Figure 3) [19]. We have previously used this catalyst successfully in our search for unsymmetrical α,ω-nucleobase

• bifunctional reactant with the monofunctional compound by using an excess of diamine (3 equiv) with respect to the acidic reactant. Nevertheless, this procedure led to problems in the purification step and partial decomposition of DMT-MM during the reaction. This was especially significant when compared to the

N-1 regioselective Michael- type addition of 5-substituted uracils to (2-hydroxyethyl) acrylate

• Sławomir Boncel,
• Dominika Osyda and
• Krzysztof Z. Walczak

Beilstein J. Org. Chem. 2007, 3, No. 40, doi:10.1186/1860-5397-3-40

• temperature, in the presence of 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium chloride (DMT-MM) which is a frequently used condensing agent.[16] The condensation required 1.1 equivalent of N-methylmorpholine as a co-catalyst. See Supporting Information File 1 for the detailed procedure. Structure