Decarboxylative 1,3-dipolar cycloaddition of amino acids for the synthesis of heterocyclic compounds

• Xiaofeng Zhang,
• Xiaoming Ma and
• Wei Zhang

Beilstein J. Org. Chem. 2023, 19, 1677–1693, doi:10.3762/bjoc.19.123

• developed a 2-azidobenzladehyde-based reaction sequence including a one-pot [3 + 2] cycloaddition, N-acylation and Staudinger/aza-Wittig reactions for the construction of pyrroloquinazolines and pyrrolobenzodiazepines [73]. The AcOH-catalyzed reaction of 2-azidobenzaldehydes, α-substituted amino acids and

New efficient synthesis of polysubstituted 3,4-dihydroquinazolines and 4H-3,1-benzothiazines through a Passerini/Staudinger/aza-Wittig/addition/nucleophilic substitution sequence

• Long Zhao,
• Mao-Lin Yang,
• Min Liu and
• Ming-Wu Ding

Beilstein J. Org. Chem. 2022, 18, 286–292, doi:10.3762/bjoc.18.32

• –Spengler-like cyclization processes [12]. Some 4-substituted 3,4-dihydroquinazolines were prepared by copper-catalyzed oxidative cross coupling of hydroxy intermediates with various nucleophiles [13]. Other 3,4-dihydroquinazolines were also obtained efficiently by intramolecular aza-Wittig reactions [14

Catalytic Wittig and aza-Wittig reactions

• Zhiqi Lao and
• Patrick H. Toy

Beilstein J. Org. Chem. 2016, 12, 2577–2587, doi:10.3762/bjoc.12.253

• Zhiqi Lao Patrick H. Toy Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong, People’s Republic of China 10.3762/bjoc.12.253 Abstract This review surveys the literature regarding the development of catalytic versions of the Wittig and aza-Wittig reactions. The first

• covers the field of related catalytic aza-Wittig reactions that are catalyzed by both phosphine oxides and phosphines. Keywords: aza-Wittig reactions; catalysis; phosphines; phosphine oxides; reduction; silanes; Wittig reactions; Introduction The Wittig reaction is a venerable transformation for

• focus of this review [5][6][7][8]. Additionally, analogous catalytic aza-Wittig reactions, in which carbon–nitrogen double bonds of imine groups are formed, will also be discussed in the second section of this review. Review Catalytic Wittig reactions A key requirement for versions of the Wittig

Multicomponent reactions: A simple and efficient route to heterocyclic phosphonates

• Mohammad Haji

Beilstein J. Org. Chem. 2016, 12, 1269–1301, doi:10.3762/bjoc.12.121

• . Some of these post-MCR transformations are: intramolecular cycloaddition reactions, Knoevenagel condensations, metathesis reactions, aza-Wittig reactions, Mitsunobu reactions, etc. [21]. Up to now, two review articles have been reported on azaheterocyclic phosphonates [22][23], but no overview article

One-pot sequential synthesis of isocyanates and urea derivatives via a microwave-assisted Staudinger–aza-Wittig reaction

• Diego Carnaroglio,
• Katia Martina,
• Giovanni Palmisano,
• Andrea Penoni,
• Claudia Domini and
• Giancarlo Cravotto

Beilstein J. Org. Chem. 2013, 9, 2378–2386, doi:10.3762/bjoc.9.274

• , Hoffman and Lossen rearrangements have been used quite often in the past and are still used for specific applications [10][11][12][13]. The Staudinger–aza-Wittig reactions have played a pivotal role in the construction of cyclic and acyclic compounds [14][15][16][17][18][19]. The replacement of phosgene

• ). Seven different azido-derivatives were synthesized from the alkyl halide and reacted via Staudinger–aza-Wittig reactions. After the PS-PPh2 was filtered, the isocyanate solution was directly subjected to an addition of 2 equiv of 3 and heated up to 70 °C in the MW reactor for 3 h. Primary alkyl and

The application of a monolithic triphenylphosphine reagent for conducting Ramirez gem-dibromoolefination reactions in flow

• Kimberley A. Roper,
• Malcolm B. Berry and
• Steven V. Ley

Beilstein J. Org. Chem. 2013, 9, 1781–1790, doi:10.3762/bjoc.9.207

• immobilising the triphenylphosphine on a solid-support [48]. A polymer-supported equivalent of triphenylphosphine has also been successfully utilised by our group and by others in batch Wittig reactions [49][50], Mitsunobu and Staudinger aza-Wittig reactions [51][52], as well as many examples concerning the

Facile synthesis of benzothiadiazine 1,1-dioxides, a precursor of RSV inhibitors, by tandem amidation/intramolecular aza-Wittig reaction

• Krishna C. Majumdar and
• Sintu Ganai

Beilstein J. Org. Chem. 2013, 9, 503–509, doi:10.3762/bjoc.9.54

• derivatives by acid-catalyzed hydrolysis; reagents and conditions: 50 mg of compound 13, 1 mL HCl, 4 mL ethanol, 80 °C, 4 h. Summary of the intramolecular aza-Wittig reactions.a Summary of the intramolecular aza-Wittig reactions in a one-pot fashion.a Generalization of intramolecular aza-Wittig reaction.a

A facile synthesis and fungicidal activities of 2-(alkylamino)-5,6-dimethylthieno[2,3-d]pyrimidin- 4(3H)-ones

• Yang-Gen Hu,
• Ai-Hua Zheng,
• Xu-Zhi Ruan and
• Ming-Wu Ding

Beilstein J. Org. Chem. 2008, 4, No. 49, doi:10.3762/bjoc.4.49

• Education, Central China Normal University, Wuhan 430079, China 10.3762/bjoc.4.49 Abstract The aza-Wittig reactions of iminophosphorane 3 with aromatic isocyanates generated carbodiimides 4, which were reacted with alkylamines under mild conditions to give a series of 2-(alkylamino)-5,6-dimethylthieno[2,3

• activities against six kinds of fungi. Keywords: 2-(alkylamino)-5,6-dimethylthieno[2,3-d]pyrimidin-4(3H)-one; aza-Wittig reaction; fungicidal activity; synthesis; Introduction Over the past ten years, aza-Wittig reactions of functionalized iminophosphoranes with isocyanates have been applied to produce