Pd-Catalyzed Regiodivergent Synthesis of Diverse Oxindoles Enabled by the Versatile Heck Reaction of Carbamoyl Chlorides

Abstract

We report herein a miscellaneous oxindole synthesis bearing an all-carbon quaternary center, enabled by Pd-catalyzed intramolecular cyclization followed by multiple intermolecular Heck reactions of both easily accessible alkene-tethered carbamoyl chlorides and olefins. This protocol obviates the use of prefunctionalized olefinic reagents, exhibits excellent functional group tolerance, and features fascinating reactive versatility.

Carbamoyl Fluoride-Enabled Enantioselective Ni-Catalyzed Carbocarbamoylation of Unactivated Alkenes

“…To break through the restriction of aromatic rings to achieve more diverse product structures, a distinctive tethered-alkene strategy proceeding via an acylmetal intermediate has also been devised (Scheme b). The strategy used carbamoyls or analogues as carbonyl sources, not only rendering the preparation of substrates easier but also allowing a more convenient product elaboration. However, major advances of the strategy have been limited to activated alkenes (typical analogues, Scheme b), , and enantioselective carbocarbamoylation of unactivated alkenes has been a formidable challenge .…”

A new synthetic approach to oxindoles (1,3-dihydro-2H-indol-2-ones) by reductive dephosphorylation with hydroiodic acid of 3-(diethylphosphoryloxy)- oxindoles, derived from isatins (1H-Indole-2,3-diones)

“…Oxindoles (1,3-dihydro-2H-indol-2-ones) are a privileged structural motif, which not only occur widely in bioactive natural products and pharmaceuticals [1][2][3][4][5][6] but are also used as synthetic intermediates for various organic transformations [7][8][9][10][11][12]. Many synthetic strategies have been established to access this skeleton, including the oxidation of indoles, [13][14][15] transition metal-catalyzed Heck-type reactions of acrylamides, [16][17][18][19][20][21][22][23][24] metalcatalyzed cyclization of o-haloacetanilides, [25][26][27][28][29] reductive desulfurization of 3-methylthiooxindoles, 30,31 double C-H oxidative coupling of functionalized acetanilides, [32][33][34][35][36][37][38][39] the C-H oxidative radical coupling of acrylanilides, [40][41][42][43] and so on (Scheme 1). Regrettably, all of the aforementioned methods inherently require a specifically functionalized precursor such as the presence of an ortho-halogen, an amino group and the...…”

Syntheses of 3,3-Disubstituted Dihydrobenzofurans, Indolines, Indolinones and Isochromanes by Palladium-Catalyzed Tandem Reaction Using Pd(PPh3)2Cl2/(±)-BINAP as a Catalytic System

“…The domino reactions of the synthesis of them were summarized mainly as follows: (i) the Pd or Ni-catalyzed cyclocarbopalladation/coupling fractions, in which the process was initiated by Heck cyclization of a starter (halide) and a relay (alkene), followed by intermolecular coupling reactions with a terminator (organometallic reagents, alkenes, alkynes, etc. ), including Suzuki, Stille, Heck, Sonogashira, C-H activation, carbonylation and amination and so forth [15][16][17]22,24,25,[29][30][31][32][33][34][35][36][37][38][39][40][41][42][43][44]; (ii) the C-H oxidative radical coupling reactions, in which these transformations were based on tandem radical addition/cyclization in the presence of oxidants with/without metal catalysts [18][19][20][21]23,26,[45][46][47][48][49][50][51][52][53][54][55]; and (iii) the other reactions [24,[56][57][58][5...…”