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In this paper, in the presence of trimethylsilyl iodide, the direct ortho -C-H hydroxyalkylation/methylation of aryl iodines was effectively realized via palladium/norbornene cooperative catalysis when low-cost tetrahydrofuran and 1,2-dimethoxyethane were used as alkyl sources. Heck, Suzuki, and Sonogashira coupling and hydrogenation were all compatible with the reaction as termination steps. In addition, neuromuscular agents and cardiovascular agents were synthesized in one step by this method, showing their potential application value.

A palladium-catalyzed crossed biaryl coupling/reduction sequence enables the formation of meta-substituted biaryls via solvent-mediated arylpalladium(II) reduction. Isotope labeling studies determined that the decomposition of 1,2-dimethoxyethane (DME) is indeed involved in the reductive process.

Generally used and highly reactive RMgBr reagents were effectively deactivated by bis[2-(N,N-dimethylamino)ethyl] ether and then were employed in the highly enantioselective addition of Grignard reagents to aldehydes. The reaction was catalyzed by the complex of commercially available (S)-BINOL and Ti(O(i-)Pr)(4) under mild conditions. Compared with the other observed Grignard reagents, alkyl Grignard reagents showed higher enantioselectivity and they achieved >99% ee.

A wide variety of 3-iodobenzo[b]furans were readily prepared by iodocyclization of 2-alkynyl-1-(1-ethoxyethoxy)benzenes with the I(coll)2PF6-BF3 x OEt2 combination. Aryl-, vinylic-, and alkyl-substituted alkynes undergo iodocyclization in good to excellent yields. The mechanism of the reaction is also discussed.

[Reaction: see text] The (R)-oxynitrilase from almonds was immobilized as a cross-linked enzyme aggregate (CLEA) via precipitation with 1,2-dimethoxyethane and subsequent cross-linking using glutaraldehyde. The resulting preparation was a highly effective hydrocyanation catalyst under microaqueous conditions, which suppress the nonenzymatic background reaction. The beneficial effect of these latter conditions on the hydrocyanation of slow-reacting aldehydes is demonstrated. The oxynitrilase CLEA was recycled 10 times without loss of activity.

[reaction: see text] For reactions of magnesium with cyclopropyl bromide in diethyl ether, added DCPH decreases the yield of cyclopropylmagnesium bromide by as much as 75%, while solvent-derived products disappear and cyclopropylcyclohexylphosphine and tetracyclohexyldiphosphine appear. These changes reflect trapping of diffusing intermediate cyclopropyl radicals.