ChemInform Abstract: Transition Metal-Free α-C(sp3)-H Bond Functionalization of Amines by Oxidative Cross Dehydrogenative Coupling Reaction: Simple and Direct Access to C-4-Alkylated 3,4-Dihydroquinazoline Derivatives.

A novel PhI(OAc)2-mediated cross-dehydrogenative coupling reaction of α-C(sp3)–H bonds adjacent to a hetero atom with various azoles has been developed, which provides an alternative method for constructing C–N bonds with high atom efficiency. This new protocol requires no metal catalyst and it provides ready access to a wide range of N-alkylated azole derivatives in moderate to excellent yields by using commercially available PhI(OAc)2 as the sole oxidant. Furthermore, the method is effective on a gram scale, which highlights the practicality of this transformation. The result of radical-captured experiments indicated that the transformation might involve a free-radical pathway.

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Oxidative cross-dehydrogenative coupling (CDC) via C(sp2)–H bond functionalization: tert-butyl peroxybenzoate (TBPB)-promoted regioselective direct C-3 acylation/benzoylation of 2H-indazoles with aldehydes/benzyl alcohols/styrenes

RSC Advances ◽

10.1039/d1ra02225c ◽

2021 ◽

Vol 11 (23) ◽

pp. 14178-14192

Author(s):

Richa Sharma ◽

Lalit Yadav ◽

Ravi Kant Yadav ◽

Sandeep Chaudhary

Keyword(s):

Transition Metal ◽

Benzyl Alcohols ◽

Bond Functionalization ◽

Metal Free ◽

Tert Butyl ◽

Dehydrogenative Coupling

An efficient transition-metal-free oxidative C(sp2)–H/C(sp2)–H cross-dehydrogenative coupling via C(sp2)–H bond functionalization for regioselective C-3 acylation/benzoylation of 2H-indazoles with aldehydes/benzyl alcohols/styrenes is reported.

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Regioselective transition metal-free acylation of coumarins via cross-dehydrogenative coupling reaction of coumarins and aldehydes

Tetrahedron Letters ◽

10.1016/j.tetlet.2016.06.061 ◽

2016 ◽

Vol 57 (33) ◽

pp. 3701-3705 ◽

Cited By ~ 8

Author(s):

Mehdi Adib ◽

Saideh Rajai-Daryasarei ◽

Rahim Pashazadeh ◽

Mahnaz Tajik ◽

Peiman Mirzaei

Keyword(s):

Transition Metal ◽

Coupling Reaction ◽

Metal Free ◽

Dehydrogenative Coupling

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Transition Metal-Free Cross-Dehydrogenative Coupling Reaction of Coumarins with Acetonitrile or Acetone

The Journal of Organic Chemistry ◽

10.1021/acs.joc.8b01508 ◽

2018 ◽

Vol 83 (21) ◽

pp. 13030-13035 ◽

Cited By ~ 21

Author(s):

Rongxing Zhang ◽

Shengzhou Jin ◽

Qian Liu ◽

Sen Lin ◽

Zhaohua Yan

Keyword(s):

Transition Metal ◽

Coupling Reaction ◽

Metal Free ◽

Dehydrogenative Coupling

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TBHP/n-Bu4PBr-Promoted Oxidative Cross-Dehydrogenative Coupling of Aryl Methanols: A Facile Synthesis of Symmetrical Carboxylic Anhydride Derivatives

Synlett ◽

10.1055/s-0036-1590905 ◽

2017 ◽

Vol 29 (01) ◽

pp. 136-140

Author(s):

Mehdi Adib ◽

Rahim Pashazadeh

Keyword(s):

Transition Metal ◽

Coupling Reaction ◽

Catalytic Amount ◽

Facile Synthesis ◽

Butyl Hydroperoxide ◽

Metal Free ◽

Tert Butyl ◽

Dehydrogenative Coupling ◽

Tert Butyl Hydroperoxide ◽

Methylene Groups

A transition-metal-free oxidative cross-dehydrogenative coupling reaction has been developed for the preparation of symmetrical carboxylic anhydrides through self-coupling dual C–O bond formations of aryl methanols. In the presence of a catalytic amount of tetrabutylphosphonium bromide (TBPB) as transfer agent and aqueous tert-butyl hydroperoxide (TBHP) as oxidant and reactant, methylene groups of aryl methanols were efficiently oxidized to C=O and coupled with the peroxide oxygen from TBHP to form a diverse array of symmetrical carboxylic anhydride derivatives.

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