An Unusual Example of a 6-Endo-Dig Addition to an Unactivated Carbon-Carbon Triple Bond

Bridging the gap between homogeneous and heterogeneous gold catalysis: supported gold nanoparticles as heterogeneous catalysts for the benzannulation reaction

“…Benzaldehyde 1 was obtained by the method employed by Padwa [23] and Dopico [24]. Pd(OAc) 2 (108 mg, 0.48 mmol), PPh 3 (218 mg, 0.83 mmol), CuI (16 mg, 0.084 mmol) and PhC " CH (8.16 g, 80 mmol) were added to a stirred solution of 2-bromobenzaldehyde (10.0 g, 54.0 mmol) in anhydrous Et 3 N (164 mL).…”

Palladium catalysed tandem cyclisation–anion capture processes. Part 8 : In situ and preformed organostannanes. Carbamyl chlorides and other starter species

“…Treatment of 1a,b with trimethylsilylacetylene under SonogashiraÕs conditions [9] afforded the desired TMS protected ethynyl derivatives 2a,b in high yield. Deprotection with TBAF [10] afforded 3a,b in 89-91% yield which were converted to the desired carbamyl chloride products 4a,b on treatment with phosgene [11] in toluene at 0°C (Scheme 1).…”

“…The residue was then passed through a column of silica eluting with 1:1 v/v diethyl ether-pentane or pure ether. The product fractions were combined and evaporated to dryness and the residual pale brown oil was dissolved in THF (170 ml), the solution cooled to 0°C, tetrabutylammonium fluoride (48.38 ml, 1.0 M in THF, 48.4 mmol) added and the mixture stirred at r.t. for 16 h [10]. The solution was then diluted with ether (150 ml), washed with sat.…”

Cyclocarbonylative Sonogashira Reactions of 1‐Ethynylbenzyl Alcohols: Synthesis of 1‐Carbonylmethylene‐1,3‐Dihydroisobenzofurans

“…They are generally based on the cyclization of functionalized substrates such as alkynyloxiranes,11 o ‐alkynylbenzaldehydes,12 and o ‐alkynylbenzyl alcohols, which are often prepared by Sonogashira coupling of iodobenzyl alcohol with terminal acetylenes. The intramolecular cyclization of alkynyl alcohols can be promoted by a base (NaH,13 KOH,14 or t BuOK15) or mediated by lanthanide,16 copper,17 or palladium18 catalysts. In this field, Gabriele and coworkers19 have developed an interesting approach based on the use of a PdI 2 /KI system.…”