Synthesis of Nonracemic β-Hydroxy Ketones and Carbonate Derivatives from Homopropargylic Alcohols through Iodolactonization

Synthesis of Densely Functionalised 5‐Halogen‐1,3‐oxazin‐2‐ones by Halogen‐Mediated Regioselective Cyclisation of N‐Cbz‐Protected Propargylic Amines: A Combined Experimental and Theoretical Study

“…1 H NMR spectroscopy was run at 300 MHz for 1 H and at 75.5 MHz for 13 C NMR in a Bruker Avance 300 DPX spectrometer. 1 H NMR spectra and 13 C NMR spectra were internally referenced to CDCl 3 signal (d = 7.26 and 77.0 ppm, respectively).…”

“…[3] This second activation method leads to the synthesis of halogen-containing heterocycle or carbocycle derivatives, which are versatile precursors in many synthetic processes. With regard to the internal nucleophile, a wide range of nucleophilic groups, such as alcohols, [4] ethers, [5] thioethers, [6] selenoethers, [7] amines, [8] imines, [9] oximes, [10] azides, [11] aldehydes and ketones, [12] carboxylic acids and their derivatives, [13] 1,3-dicarbonyl compounds [14] and aromatic rings, [15] has been investigated. However, the use of functionalised alkynes possessing a carbamate derivative as the internal nucleophilic group remains relatively unexplored.…”

Synthesis of tetrasubstituted olefins and aryl ketones via carbopalladation of alkynes and nitriles

“…The use of TFA as solvent is apparently crucial for the success of this chemistry, since none of the desired product was obtained when acetic acid was employed as the solvent (entry 11). Other Pd catalysts, such as PdOL(PPh^)2, Pd(PPh^ and Pd/C, are ineffective in this chemistry (entries [12][13][14]. The Pd(II) catalyst is uniquely effective, since other late transition metal salts or common Lewis acids all failed to give any of the desired product (entries [15][16][17][18][19][20][21][22].…”

“…13 As an application of our chemistry, a simple approach to xanthones has been developed, which involves ketone formation using simple phenols and 2-fluorobenzonitrile as starting materials, followed by intramolecular cyclization under mild conditions (eq. 3).…”

“…1 Tetrasubstituted olefins can be obtained by carbonyl olefmation reactions 2 " 5 (including McMurry, 3 Wittig, 4 and HornerWadsworth-Emmons 5 reactions), olefin metathesis 6 and various other methods (including cycloaddition, 7 dehydration, 8 ynolate anions, 9 vinylic radical chemistry, 10 etc.). Reactions involving trisubstituted vinylic metal substrates (metal = B, 11 Si, 12 S, 13 Zr, 14 Sn, 15 Te, 16 etc. ) or intermediates (metal = Li, 17 Mg, 18 Ni, 19 Cu, 20 Zn, 21 Pd, 22 etc.)…”