A High-Yield, General Method for the Catalytic Formation of Oxygen Heterocycles

Palladium‐Catalyzed CN and CO Coupling–A Practical Guide from an Industrial Vantage Point†

“…The Buchwald group also published procedures with new ligand structures, usually containing two tertbutyl groups and a bulky polyaromatic system. [129,130] These ligands work equally well for aryl chlorides as starting materials [69,126 -128,130,131] as for primary alcohols [69,128,130,132,133] with aryl bromides. Interesting to note is the fact that so far aryl chlorides have only been coupled with primary alcohols using the Buchwald ligand family.…”

“…Interesting to note is the fact that so far aryl chlorides have only been coupled with primary alcohols using the Buchwald ligand family. [130,132,133] Next to the coupling of aliphatic alcohols with aryl halides, the formation of diaryl ethers has reached good applicability, mainly using Hartwigs Q-Phos [69] or the Buchwald ligands. [129] For the direct exchange of a halogen with a hydroxy group, either the formation of a tert-butyl ether with acidic work-up [127] or the introduction of a silyl-protected alcohol [69,128] were suggested.…”

“…[134] More recent publications, however, also disclosed protocols using both Hartwigs Q-Phos or members of the Buchwald family. [69,128,130,133] Only very few examples of successful coupling of pyridyl halides with aliphatic alcohols have been described, those using either P(tBu) 3 [126] or the Buchwald ligands. [132] Only prophyrins as representatives of other heteroaromatic aryl halides have been used to generate the corresponding aryl ethers, in that case using DPEPhos as ligand.…”

Factors affecting the lability of the σ(M–X) bond in cycloplatinated and cyclopalladated complexes containing [C(sp2, ferrocene),N,X]− or [C(sp2, phenyl),N,X]− (X=S, N) terdentate ligands

“…Cyclometallated complexes containing platinum(II) or palladium(II) ligands [1] have generated considerable interest since long ago mainly due to their applications in homogeneous catalysis or for the design of new materials with outstanding properties [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18]. Their utility as precursors in organic and organometallic synthesis [13][14][15][16][17][18] is also well-known.…”

Reductive Elimination of Ether from T‐Shaped, Monomeric Arylpalladium Alkoxides

“…Only reductive eliminations of alkyl aryl ethers from complexes generated in situ, reductive elimination of an oxygen heterocycle from a single oxapalladacycle,[2] reductive eliminations from arylpalladium alkoxides containing activating groups on the aryl ring, [3,4] and reductive eliminations of biaryl ethers in low yield from isolated complexes [5,6] are documented. Most importantly, the most active catalysts for the palladium-catalyzed etherification of aryl halides contain sterically hindered monophosphines, [1,[6][7][8][9][10][11][12][13][14][15] and no reductive eliminations from arylpalladium alkoxides containing hindered monophosphines have been described.We report reductive eliminations from isolated and structurally characterized examples of such arylpalladium alkoxides. We show that reductive eliminations occur from the observed species containing one aryl, one alkoxide, and one phosphine ligand.…”