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• W3136172456 endingPage "4836" @default.
• W3136172456 startingPage "4824" @default.
• W3136172456 abstract "The selective synthesis of Z-alkenes in alkyne semihydrogenation relies on the reactivity difference of the catalysts toward the starting materials and the products. Here we report Z-selective semihydrogenation of alkynes with ethanol via a coordination-induced ionic monohydride mechanism. The EtOH-coordination-driven Cl- dissociation in a pincer Ir(III) hydridochloride complex (NCP)IrHCl (1) forms a cationic monohydride, [(NCP)IrH(EtOH)]+Cl-, that reacts selectively with alkynes over the corresponding Z-alkenes, thereby overcoming competing thermodynamically dominant alkene Z-E isomerization and overreduction. The challenge for establishing a catalytic cycle, however, lies in the alcoholysis step; the reaction of the alkyne insertion product (NCP)IrCl(vinyl) with EtOH does occur, but very slowly. Surprisingly, the alcoholysis does not proceed via direct protonolysis of the Ir-C(vinyl) bond. Instead, mechanistic data are consistent with an anion-involved alcoholysis pathway involving ionization of (NCP)IrCl(vinyl) via EtOH-for-Cl substitution and reversible protonation of Cl- ion with an Ir(III)-bound EtOH, followed by β-H elimination of the ethoxy ligand and C(vinyl)-H reductive elimination. The use of an amine is key to the monohydride mechanism by promoting the alcoholysis. The 1-amine-EtOH catalytic system exhibits an unprecedented level of substrate scope, generality, and compatibility, as demonstrated by Z-selective reduction of all alkyne classes, including challenging enynes and complex polyfunctionalized molecules. Comparison with a cationic monohydride complex bearing a noncoordinating BArF- ion elucidates the beneficial role of the Cl- ion in controlling the stereoselectivity, and comparison between 1-amine-EtOH and 1-NaOtBu-EtOH underscores the fact that this base variable, albeit in catalytic amounts, leads to different mechanisms and consequently different stereoselectivity." @default.
• W3136172456 created "2021-03-29" @default.
• W3136172456 creator A5010215438 @default.
• W3136172456 creator A5033486450 @default.
• W3136172456 creator A5035062653 @default.
• W3136172456 creator A5058005813 @default.
• W3136172456 date "2021-03-16" @default.
• W3136172456 modified "2023-10-12" @default.
• W3136172456 title "An Amine-Assisted Ionic Monohydride Mechanism Enables Selective Alkyne <i>cis</i>-Semihydrogenation with Ethanol: From Elementary Steps to Catalysis" @default.
• W3136172456 cites W136347255 @default.
• W3136172456 cites W1589506408 @default.
• W3136172456 cites W1964060855 @default.
• W3136172456 cites W1980512236 @default.
• W3136172456 cites W1985842075 @default.
• W3136172456 cites W1988314193 @default.
• W3136172456 cites W1989455380 @default.
• W3136172456 cites W1989623313 @default.
• W3136172456 cites W1993048542 @default.
• W3136172456 cites W1993851202 @default.
• W3136172456 cites W2000432537 @default.
• W3136172456 cites W2002507671 @default.
• W3136172456 cites W2003180722 @default.
• W3136172456 cites W2004049068 @default.
• W3136172456 cites W2005005430 @default.
• W3136172456 cites W2011664450 @default.
• W3136172456 cites W2012434444 @default.
• W3136172456 cites W2015253591 @default.
• W3136172456 cites W2018014134 @default.
• W3136172456 cites W2018653077 @default.
• W3136172456 cites W2023267789 @default.
• W3136172456 cites W2046141105 @default.
• W3136172456 cites W2048022307 @default.
• W3136172456 cites W2048955718 @default.
• W3136172456 cites W2058911496 @default.
• W3136172456 cites W2060178373 @default.
• W3136172456 cites W2061249879 @default.
• W3136172456 cites W2061630997 @default.
• W3136172456 cites W2062714224 @default.
• W3136172456 cites W2066671943 @default.
• W3136172456 cites W2071755467 @default.
• W3136172456 cites W2078112572 @default.
• W3136172456 cites W2083758257 @default.
• W3136172456 cites W2087428925 @default.
• W3136172456 cites W2090604189 @default.
• W3136172456 cites W2094483101 @default.
• W3136172456 cites W2115809286 @default.
• W3136172456 cites W2137260662 @default.
• W3136172456 cites W2139661138 @default.
• W3136172456 cites W2140330959 @default.
• W3136172456 cites W2147957964 @default.
• W3136172456 cites W2154881052 @default.
• W3136172456 cites W2163731799 @default.
• W3136172456 cites W2171029215 @default.
• W3136172456 cites W2171903404 @default.
• W3136172456 cites W2181974339 @default.
• W3136172456 cites W2273726404 @default.
• W3136172456 cites W2300210424 @default.
• W3136172456 cites W2300306696 @default.
• W3136172456 cites W2302054269 @default.
• W3136172456 cites W2316261853 @default.
• W3136172456 cites W2317059881 @default.
• W3136172456 cites W2319591202 @default.
• W3136172456 cites W2320153655 @default.
• W3136172456 cites W2321381449 @default.
• W3136172456 cites W2321855466 @default.
• W3136172456 cites W2326844497 @default.
• W3136172456 cites W2327379756 @default.
• W3136172456 cites W2333875011 @default.
• W3136172456 cites W2409715021 @default.
• W3136172456 cites W2463295065 @default.
• W3136172456 cites W2464305446 @default.
• W3136172456 cites W2466353001 @default.
• W3136172456 cites W2476964187 @default.
• W3136172456 cites W2516114369 @default.
• W3136172456 cites W2541115510 @default.
• W3136172456 cites W2541655125 @default.
• W3136172456 cites W2553999568 @default.
• W3136172456 cites W2564473732 @default.
• W3136172456 cites W2564485381 @default.
• W3136172456 cites W2573197589 @default.
• W3136172456 cites W2601224882 @default.
• W3136172456 cites W2626230063 @default.
• W3136172456 cites W2752298109 @default.
• W3136172456 cites W2760777285 @default.
• W3136172456 cites W2767304235 @default.
• W3136172456 cites W2778427729 @default.
• W3136172456 cites W2792520247 @default.
• W3136172456 cites W2793395299 @default.
• W3136172456 cites W2794668600 @default.
• W3136172456 cites W2805155466 @default.
• W3136172456 cites W2912628160 @default.
• W3136172456 cites W2937095813 @default.
• W3136172456 cites W2949148477 @default.
• W3136172456 cites W2949876756 @default.
• W3136172456 cites W2979568257 @default.
• W3136172456 cites W3009075473 @default.
• W3136172456 cites W3026296218 @default.
• W3136172456 cites W3040785879 @default.

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