Manganese-Catalyzed α-Alkylation of Ketones, Esters, and Amides Using Alcohols

ACS Catalysis, Год журнала: 2018, Номер 8(11), С. 10300 - 10305

Опубликована: Окт. 2, 2018

Herein we report the manganese-catalyzed C–C bond-forming reactions via α-alkylation of ketones, amides, and esters, using primary alcohols. β-Alkylation secondary alcohols by to obtain α-alkylated ketones is also reported. The are catalyzed a (iPr-PNP)Mn(H)(CO)2 pincer complex under mild conditions in presence (catalytic) base liberating water (and H2 case alcohol alkylation) as sole byproduct.

Язык: Английский

---

Alcohols as Substrates in Transition-Metal-Catalyzed Arylation, Alkylation, and Related Reactions

Chemical Reviews, Год журнала: 2024, Номер 124(9), С. 6078 - 6144

Опубликована: Апрель 17, 2024

Alcohols are abundant and attractive feedstock molecules for organic synthesis. Many methods their functionalization require them to first be converted into a more activated derivative, while recent years have seen vast increase in the number of complexity-building transformations that directly harness unprotected alcohols. This Review discusses how transition metal catalysis can used toward this goal. These broadly classified three categories. Deoxygenative functionalizations, representing derivatization C–O bond, enable alcohol act as leaving group formation new C–C bonds. Etherifications, characterized by O–H represent classical reactivity has been modernized include mild reaction conditions, diverse partners, high selectivities. Lastly, chain reactions described, wherein acts mediator formal C–H alkyl backbone. Each these classes transformation will discussed context intermolecular arylation, alkylation, related reactions, illustrating alcohols harnessed

Язык: Английский

---

Manganese-Catalyzed β-Alkylation of Secondary Alcohols with Primary Alcohols under Phosphine-Free Conditions

ACS Catalysis, Год журнала: 2018, Номер 8(8), С. 7201 - 7207

Опубликована: Июль 5, 2018

Manganese(I) complexes bearing a pyridyl-supported pyrazolyl-imidazolyl ligand efficiently catalyzed the direct β-alkylation of secondary alcohols with primary under phosphine-free conditions. The β-alkylated were obtained in moderate to good yields water formed as byproduct through borrowing hydrogen pathway. β-Alkylation cholesterols was also effectively achieved. present protocol provides concise atom-economical method for C–C bond formation from and alcohols.

Язык: Английский

---

Phosphine‐Free NNN‐Manganese Complex Catalyzed α‐Alkylation of Ketones with Primary Alcohols and Friedländer Quinoline Synthesis

Advanced Synthesis & Catalysis, Год журнала: 2018, Номер 360(17), С. 3233 - 3238

Опубликована: Июнь 29, 2018

Abstract Herein, we report a very simple and inexpensive catalytic system based on Earth's abundant transition metal manganese bench‐stable phosphine‐free NNN‐pincer ligand for an atom‐efficient α‐alkylations of ketones with primary alcohols via hydrogen‐autotransfer C−C bond formation protocol. The precatalyst could be generated in situ activated by using amount base under milder conditions. A range were efficiently diversified broad good to excellent isolated yields. Remarkably, this catalyst also employed the synthesis quinoline derivatives 2‐aminobenzyl alcohol as alkylating agent. later reaction is highly benign producing only hydrogen water byproducts. magnified image

Язык: Английский

---

Cobalt complex catalyzed atom-economical synthesis of quinoxaline, quinoline and 2-alkylaminoquinoline derivatives

Chemical Communications, Год журнала: 2018, Номер 54(50), С. 6883 - 6886

Опубликована: Янв. 1, 2018

A new phosphine-free Co(ii) complex-catalyzed synthesis of various quinoxalines via dehydrogenative coupling vicinal diols with both o-phenylenediamines and 2-nitroanilines is reported. This complex was also effective for the quinolines. The practical aspect this catalytic system revealed by one-pot 2-alkylaminoquinolines.

Язык: Английский

---

Catalytic Cross-Coupling of Secondary Alcohols

Journal of the American Chemical Society, Год журнала: 2019, Номер 141(9), С. 3822 - 3827

Опубликована: Фев. 21, 2019

Herein, an unprecedented ruthenium(II) catalyzed direct cross-coupling of two different secondary alcohols to β-disubstituted ketones is reported. Cyclic, acylic, symmetrical, and unsymmetrical are selectively coupled with aromatic benzylic provide ketone products. A single catalyst oxidizes both broaden the scope this catalytic protocol. Number bond activation formation reactions occur in selective sequence via amine-amide metal-ligand cooperation operative Ru-MACHO catalyst. The product-induced diastereoselectivity was also observed. Kinetic deuterium labeling experiments suggested that aliphatic undergo oxidation reaction faster than alcohols, assimilating cross-coupled Reactions sensitive steric hindrance. This new C-C forming methodology requires low load amount base. Notably, produces H2 H2O as only byproducts making protocol greener, atom economical environmentally benign.

Язык: Английский

---

Nonbifunctional Outer-Sphere Strategy Achieved Highly Active α-Alkylation of Ketones with Alcohols by N-Heterocyclic Carbene Manganese (NHC-Mn)

Organic Letters, Год журнала: 2019, Номер 21(19), С. 8065 - 8070

Опубликована: Сен. 16, 2019

The unusual nonbifunctional outer-sphere strategy was successfully utilized in developing an easily accessible N-heterocyclic carbene manganese (NHC-Mn) system for highly active α-alkylation of ketones with alcohols. This efficient a wide range and alcohols under mild reaction conditions, also the green synthesis quinoline derivatives. direct mechanism high activity present demonstrate potential catalyst design acceptorless dehydrogenative transformations.

Язык: Английский

---

Metal–Ligand Cooperative Approach To Achieve Dehydrogenative Functionalization of Alcohols to Quinolines and Quinazolin-4(3H)-ones under Mild Aerobic Conditions

The Journal of Organic Chemistry, Год журнала: 2019, Номер 84(16), С. 10160 - 10171

Опубликована: Июль 22, 2019

A simple metal–ligand cooperative approach for the dehydrogenative functionalization of alcohols to various substituted quinolines and quinazolin-4(3H)-ones under relatively mild reaction conditions (≤90 °C) is reported. Simple easy-to-prepare air-stable Cu(II) complexes featuring redox-active azo-aromatic scaffolds, 2-arylazo-(1,10-phenanthroline) (L1,2), are used as catalyst. wide variety were synthesized in moderate good isolated yields via coupling reactions inexpensive easily available starting materials aerobic conditions. few control experiments deuterium labeling studies carried out understand mechanism reactions, which indicate that both copper coordinated ligand participate a manner during catalytic cycle.

Язык: Английский

---

Iridium(I)-Catalyzed C–C and C–N Bond Formation Reactions via the Borrowing Hydrogen Strategy

The Journal of Organic Chemistry, Год журнала: 2019, Номер 84(10), С. 6286 - 6297

Опубликована: Апрель 15, 2019

Iridium(I) complexes having an imidazol-2-ylidene ligand with benzylic wingtips efficiently catalyzed the β-alkylation of secondary alcohols primary and acceptorless dehydrogenative cyclization 2-aminobenzyl alcohol ketones through a borrowing hydrogen pathway. The β-alkylated alcohols, including cholesterol derivatives, substituted quinolines were obtained in good yields by using minute amount catalyst catalytic NaOH or KOH under air atmosphere, liberating water (and H2 case quinoline synthesis) as sole byproduct. Notably, this system demonstrated turnover numbers 940 000 (for down to 0.0001 mol % = 1 ppm catalyst) 9200 (acceptorless ketones).

Язык: Английский

---

Selective Catalytic Synthesis of α-Alkylated Ketones and β-Disubstituted Ketones via Acceptorless Dehydrogenative Cross-Coupling of Alcohols

Organic Letters, Год журнала: 2021, Номер 23(3), С. 869 - 875

Опубликована: Янв. 21, 2021

Herein, a phosphine-free pincer ruthenium(III) catalyzed β-alkylation of secondary alcohols with primary to α-alkylated ketones and two different β-branched are reported. Notably, this transformation is environmentally benign atom efficient H2O H2 gas as the only byproducts. The protocol extended gram-scale reaction for functionalization complex vitamin E cholesterol derivatives.

Язык: Английский

---