One-pot synthesis of trifluoroacetimidoyl halides

Efficient Synthesis of the Lewis A Tandem Repeat

“…After desilylation of 11, the resulting hemiacetal 12 was treated with (N-phenyl)trifluoroacetimidoyl chloride [19] and K2CO3 to obtain (N-phenyl)trifluoroacetimidate 13. Acceptor 14 was prepared by selective deallylation with iridium-catalyzed olefin migration, followed by treatment with HgCl2 and HgO in aqueous acetone solution [20].…”

“…Compound 16 (97 mg, 42.9 μmol) was reacted with (N-phenyl)-2,2,2-trifluoroacetoimidoyl chloride (17.8 mg, 85.8 μmol) and K2CO3 (29.7 mg, 215 μmol) in acetone (1.7 mL) as described for 13. The crude product was purified by silica gel column chromatography with hexane-EtOAc (83:17) and gel permeation chromatography (19). To a mixture of the glycosyl donor 17 (276 mg, 113 μmol), the glycosyl acceptor 18 (210 mg, 85.0 μmol), and molecular sieves AW-300 (255 mg) in CH2Cl2 (2.8 mL) was added dropwise TMSOTf (3.0 μL, 17.0 μmol) at 0 °C under Ar, and stirred for 1 h at 0 °C.…”

“…The combined organic layer was successively washed with brine, dried over Na2SO4, and concentrated. The (19). To a mixture of the glycosyl donor 17 (276 mg, 113 µmol), the glycosyl acceptor 18 (210 mg, 85.0 µmol), and molecular sieves AW-300 (255 mg) in CH 2 Cl 2 (2.8 mL) was added dropwise TMSOTf (3.0 µL, 17.0 µmol) at 0˝C under Ar, and stirred for 1 h at 0˝C.…”

Studies on organophosphorus compounds 101. A facile synthetic route to trifluoromethylated aminophosphonic acids and phosphonopeptides

“…The key intermediates, trifluoromethyl N-substituted imidoyl chlorides (1), were conveniently prepared by amidation of trifluoroacetic acid with a primary amine in the presence of carbon tetrachloride, triphenylphosphine, and triethylamine in a one-pot procedure as summarized (Table 1) [7].…”

A stereocontrolled access to functionalized cispentacins and acyclic β2,3-amino acids through oxidative ring cleavage

“…The synthetic protocol used for the preparation of the imidoyl chlorides was previously described by Uneyama et al 75 . The first step in the Fustero synthesis, depicted in The high diastereoselectivity can be envisioned in terms of a proposed model (Figure 3), wherein the lowest energy transition state belongs to the α,β-unsaturated ester with an s-cis conformation.…”