Matches in SemOpenAlex for { <https://semopenalex.org/work/W2474839346> ?p ?o ?g. }
- W2474839346 endingPage "9031" @default.
- W2474839346 startingPage "9022" @default.
- W2474839346 abstract "Transition metal-catalyzed C-H bond halogenation is an important alternative to the highly utilized directed-lithiation methods and increases the accessibility of the synthetically valuable aryl halide compounds. However, this approach often requires impractical reagents, such as IOAc, or strong co-oxidants. Therefore, the development of methodology utilizing inexpensive oxidants and catalyst containing earth-abundant transition metals under mild experimental conditions would represent a significant advance in the field. Success in this endeavor requires a full understanding of the mechanisms and reactivity governing principles of this process. Here, we report intimate mechanistic details of the Pd(II)-catalyzed C-H iodination with molecular I2 as the sole oxidant. Namely, we elucidate the impact of the: (a) Pd-directing group (DG) interaction, (b) nature of oxidant, and (c) nature of the functionalized C-H bond [C(sp(2))-H vs C(sp(3))-H] on the Pd(II)/Pd(IV) redox and Pd(II)/Pd(II) redox-neutral mechanisms of this reaction. We find that both monomeric and dimeric Pd(II) species may act as an active catalyst during the reaction, which preferentially proceeds via the Pd(II)/Pd(II) redox-neutral electrophilic cleavage (EC) pathway for all studied substrates with a functionalized C(sp(2))-H bond. In general, a strong Pd-DG interaction increases the EC iodination barrier and reduces the I-I oxidative addition (OA) barrier. However, the increase in Pd-DG interaction alone is not enough to make the mechanistic switch from EC to OA: This occurs only upon changing to substrates with a functionalized C(sp(3))-H bond. We also investigated the impact of the nature of the electrophile on the C(sp(2))-H bond halogenation. We predicted molecular bromine (Br2) to be more effective electrophile for the C(sp(2))-H halogenation than I2. Subsequent experiments on the stoichiometric C(sp(2))-H bromination by Pd(OAc)2 and Br2 confirmed this prediction.The findings of this study advance our ability to design more efficient reactions with inexpensive oxidants under mild experimental conditions." @default.
- W2474839346 created "2016-07-22" @default.
- W2474839346 creator A5012743614 @default.
- W2474839346 creator A5016617077 @default.
- W2474839346 creator A5038397278 @default.
- W2474839346 creator A5052675433 @default.
- W2474839346 creator A5080816898 @default.
- W2474839346 creator A5088202689 @default.
- W2474839346 date "2015-07-14" @default.
- W2474839346 modified "2023-10-09" @default.
- W2474839346 title "Mechanistic Details of Pd(II)-Catalyzed C–H Iodination with Molecular I<sub>2</sub>: Oxidative Addition vs Electrophilic Cleavage" @default.
- W2474839346 cites W1963768535 @default.
- W2474839346 cites W1966182479 @default.
- W2474839346 cites W1967431172 @default.
- W2474839346 cites W1969142039 @default.
- W2474839346 cites W1972805076 @default.
- W2474839346 cites W1972897212 @default.
- W2474839346 cites W1973723910 @default.
- W2474839346 cites W1976900023 @default.
- W2474839346 cites W1978686301 @default.
- W2474839346 cites W1980934047 @default.
- W2474839346 cites W1983357954 @default.
- W2474839346 cites W1987207730 @default.
- W2474839346 cites W1989843389 @default.
- W2474839346 cites W1990272638 @default.
- W2474839346 cites W1991200342 @default.
- W2474839346 cites W1995042715 @default.
- W2474839346 cites W1995455836 @default.
- W2474839346 cites W1999875615 @default.
- W2474839346 cites W2006758620 @default.
- W2474839346 cites W2009962909 @default.
- W2474839346 cites W2010518405 @default.
- W2474839346 cites W2011976466 @default.
- W2474839346 cites W2012780101 @default.
- W2474839346 cites W2015723183 @default.
- W2474839346 cites W2016755677 @default.
- W2474839346 cites W2020285150 @default.
- W2474839346 cites W2020709872 @default.
- W2474839346 cites W2024183914 @default.
- W2474839346 cites W2024407161 @default.
- W2474839346 cites W2025953209 @default.
- W2474839346 cites W2029177676 @default.
- W2474839346 cites W2029961407 @default.
- W2474839346 cites W2035118396 @default.
- W2474839346 cites W2035692093 @default.
- W2474839346 cites W2037493944 @default.
- W2474839346 cites W2038083805 @default.
- W2474839346 cites W2040338102 @default.
- W2474839346 cites W2043011398 @default.
- W2474839346 cites W2044490585 @default.
- W2474839346 cites W2044574828 @default.
- W2474839346 cites W2056329441 @default.
- W2474839346 cites W2059003011 @default.
- W2474839346 cites W2063086356 @default.
- W2474839346 cites W2063255895 @default.
- W2474839346 cites W2063853756 @default.
- W2474839346 cites W2065970229 @default.
- W2474839346 cites W2066309940 @default.
- W2474839346 cites W2067433167 @default.
- W2474839346 cites W2068617439 @default.
- W2474839346 cites W2068860009 @default.
- W2474839346 cites W2069011962 @default.
- W2474839346 cites W2071765830 @default.
- W2474839346 cites W2073999814 @default.
- W2474839346 cites W2077818578 @default.
- W2474839346 cites W2078403880 @default.
- W2474839346 cites W2078965405 @default.
- W2474839346 cites W2082705160 @default.
- W2474839346 cites W2083618394 @default.
- W2474839346 cites W2084924805 @default.
- W2474839346 cites W2085399365 @default.
- W2474839346 cites W2087960929 @default.
- W2474839346 cites W2088388835 @default.
- W2474839346 cites W2092328284 @default.
- W2474839346 cites W2093731515 @default.
- W2474839346 cites W2096024006 @default.
- W2474839346 cites W2098936752 @default.
- W2474839346 cites W2099531933 @default.
- W2474839346 cites W2101204456 @default.
- W2474839346 cites W2103861098 @default.
- W2474839346 cites W2113178062 @default.
- W2474839346 cites W2114289051 @default.
- W2474839346 cites W2114862194 @default.
- W2474839346 cites W2122480383 @default.
- W2474839346 cites W2123101018 @default.
- W2474839346 cites W2123386023 @default.
- W2474839346 cites W2138256041 @default.
- W2474839346 cites W2139552174 @default.
- W2474839346 cites W2143043910 @default.
- W2474839346 cites W2144600844 @default.
- W2474839346 cites W2147599451 @default.
- W2474839346 cites W2150367833 @default.
- W2474839346 cites W2150805674 @default.
- W2474839346 cites W2151245295 @default.
- W2474839346 cites W2152353957 @default.
- W2474839346 cites W2155200603 @default.
- W2474839346 cites W2156091414 @default.
- W2474839346 cites W2159234709 @default.