Palladium‐Catalyzed Addition of Silyl‐Substituted Chloroalkynes to Terminal Alkynes

Highly efficient access to 4-chloro-2H-chromenes and 1,2-dihydroquinolines under mild conditions: TMSCl-mediated cyclization of 2-propynolphenols/anilines

“…Moreover, the synthetic application of the 4-chloro-2Hchromene products was demonstrated by an array of palladium-catalyzed cross-coupling reactions (Scheme 3). [14] Suzuki-Miyaura coupling of 2b with arylboronic acid proceeded by using L1 as the ligand to yield 7 in good yields (Scheme 3a). The products 2b also underwent Sonogashira coupling with 4-methoxyphenylacetylene by using L2 as the ligand to provide 8 in moderate yields (Scheme 3b).…”

Palladium‐Catalyzed Bromoalkynylation of CC Double Bonds: Ring‐Structure‐Dependent Synthesis of 7‐Alkynyl Norbornanes and Cyclobutenyl Halides

“…The direct cleavage of an alkynylhalogen bond followed by the reconnection of both the alkynyl and halogen ions with the two carbon atoms of an unsaturated carbon-carbon bond provides ready access to highly functionalized products from simple alkynes with excellent atom economy. [1] We previously achieved highly regio-and stereoselective bromoalkynylation of internal alkynes for the synthesis of conjugated cis-bromoalkenynes. [2] Subsequent research on this subject revealed a further use of bromoalkynes in complex molecule synthesis.…”

Palladium‐Catalyzed Alkynylthiolation of Alkynes with Triisopropylsilylethynyl Sulfide

“…In analogy with our previous report,9a the triisopropylsilyl group of 2a was essential to attain satisfactory yields. The reactions of the triethylsilyl analog 2b and the tert ‐butyldimethylsilyl analog 2c furnished the corresponding products 3ab and 3ac in lower yields (Table 1, entries 2 and 3).…”