Recent advances in synthetic approaches for bioactive cinnamic acid derivatives

• Betty A. Kustiana,
• Galuh Widiyarti and
• Teni Ernawati

Beilstein J. Org. Chem. 2025, 21, 1031–1086, doi:10.3762/bjoc.21.85

Using the phospha-Michael reaction for making phosphonium phenolate zwitterions

• Matthias R. Steiner,
• Max Schmallegger,
• Larissa Donner,
• Johann A. Hlina,
• Christoph Marschner,
• Judith Baumgartner and
• Christian Slugovc

Beilstein J. Org. Chem. 2024, 20, 41–51, doi:10.3762/bjoc.20.6

• powerful tool for performing organic reactions [1] and polymerizations [2]. In this context phosphines have proven to be potent Lewis-base catalysts [3][4] for a variety of reactions [5], including but not limited to Rauhut–Currier [6], Morita–Baylis–Hillman [7], and Michael reactions [8][9][10]. In all

An accelerated Rauhut–Currier dimerization enabled the synthesis of (±)-incarvilleatone and anticancer studies

• Tharun K. Kotammagari,
• Sweta Misra,
• Sayantan Paul,
• Sunita Kunte,
• Rajesh G. Gonnade,
• Manas K. Santra and
• Asish K. Bhattacharya

Beilstein J. Org. Chem. 2023, 19, 204–211, doi:10.3762/bjoc.19.19

• The total synthesis of racemic incarvilleatone has been achieved by utilizing unexplored accelerated Rauhut–Currier (RC) dimerization. The other key steps of the synthesis are oxa-Michael and aldol reactions in a tandem sequence. Racemic incarvilleatone was separated by chiral HPLC and the

• nonetheless, they exhibited very limited growth suppression activity. Keywords: dimerization; incarviditone; incarvilleatone; oxa-Michael; Rauhut–Currier; Introduction (±)-Incarvilleatone (1) is a dimeric cyclohexylethanoid isolated by Zhang and co-workers [1] in racemic form from the Chinese plant

• (±)-rengyolone (3). Despite of these syntheses, the synthesis of the dimeric natural product (±)-incarvilleatone (1), whose monomeric unit (±)-rengyolone (3) was connected by accelerated intermolecular Rauhut–Currier (RC) reaction was not reported in literature. Herein, we present the total synthesis of

Oxa-Michael-initiated cascade reactions of levoglucosenone

• Julian Klepp,
• Thomas Bousfield,
• Hugh Cummins,
• Sarah V. A.-M. Legendre,
• Jason E. Camp and
• Ben W. Greatrex

Beilstein J. Org. Chem. 2022, 18, 1457–1462, doi:10.3762/bjoc.18.151

• processes in 1, such as the Baylis–Hillman reaction [14], and the Rauhut–Currier reaction which gives dimers such as 2 as well as higher oligomers [10][15]. An oxa-Michael-initiated three-component intermolecular reaction of 1 with furfural and water has been reported to result in enone 3 (Figure 1) [16

• elimination of methanol rather than exocyclic elimination of water, and regioisomeric Rauhut–Currier reaction. Compound 7 was found to be unstable after isolation, possibly due to intermolecular reactions of the electron-poor olefin and furan ring. When a slight excess of 1 was used, only 6n was isolated

• presumed to start with an oxa-Michael initiated aldol reaction promoted by a methoxide nucleophile giving enone 6 via enolate 8 (Scheme 1). A Rauhut–Currier-type reaction of 6 with the addition of another equivalent of 8, followed by a subsequent double β-elimination leads to the observed product 5. When

A Se···O bonding catalysis approach to the synthesis of calix[4]pyrroles

• Qingzhe Tong,
• Zhiguo Zhao and
• Yao Wang

Beilstein J. Org. Chem. 2022, 18, 325–330, doi:10.3762/bjoc.18.36

• phosphonium selenide catalysts which showed catalytic activity in assembly reactions [41], Michael addition reactions [41], Rauhut–Currier reactions [42], cyanosilylation reactions [43], and cycloaddition of vinylindoles through chalcogen–π bonding catalysis [44]. Our previous works demonstrated that Se···O

Electron-rich triarylphosphines as nucleophilic catalysts for oxa-Michael reactions

• Susanne M. Fischer,
• Simon Renner,
• A. Daniel Boese and
• Christian Slugovc

Beilstein J. Org. Chem. 2021, 17, 1689–1697, doi:10.3762/bjoc.17.117

• masses of about 1200 g/mol at room temperature are accessible. Polymerizations carried out at 80 °C resulted in macromolecules containing a considerable share of Rauhut–Currier-type repeat units and consequently lower molar masses were obtained. Keywords: Michael acceptor affinity; Michael addition

• chemistry; organocatalysis; phosphine; solvent-free synthesis; Introduction Phosphines are potent nucleophiles that are used as catalysts in many reactions, like Rauhut–Currier, Morita–Baylis–Hillman or Michael reactions [1][2][3]. The first step of these reactions is a conjugate addition of the phosphine

• evaluation of the NMR spectra indicate, among repeating units from oxa-Michael and transesterification reactions [30][31], the presence of Rauhut–Currier-derived linkages [32][33][34]. This repeat unit is characterized by peaks at 6.22 and 5.64 ppm in the 1H NMR spectrum and at 126.6, 33.0, 27.3 ppm in the

Phosphazene-catalyzed desymmetrization of cyclohexadienones by dithiane addition

• Matthew A. Horwitz,
• Elisabetta Massolo and
• Jeffrey S. Johnson

Beilstein J. Org. Chem. 2017, 13, 762–767, doi:10.3762/bjoc.13.75

• ] nucleophiles using bifunctional cinchona alkaloid catalysts. The Sasai and Enders groups used a phosphinothiourea to enable a Rauhut–Currier reaction to form bicyclic enones [16]. The Tian and Lin group used alkyne-tethered cyclohexadienones in an arylrhodation/conjugate addition sequence that

Asymmetric α-amination of 3-substituted oxindoles using chiral bifunctional phosphine catalysts

• Qiao-Wen Jin,
• Zhuo Chai,
• You-Ming Huang,
• Gang Zou and
• Gang Zhao

Beilstein J. Org. Chem. 2016, 12, 725–731, doi:10.3762/bjoc.12.72

• a variety of reactions such as aza-Morita–Baylis–Hillman reactions [19][20][21], Rauhut–Currier reactions [22][23][24][25][26][27], Michael addition reactions [28][29][30][31][32][33][34][35], and various cycloadditions [36][37][38][39]. In recent years, our group has focused on the development of

Chiral phosphines in nucleophilic organocatalysis

• Yumei Xiao,
• Zhanhu Sun,
• Hongchao Guo and
• Ohyun Kwon

Beilstein J. Org. Chem. 2014, 10, 2089–2121, doi:10.3762/bjoc.10.218

• acylations of alcohols. Our discussion is organized according to the structural features of the chiral phosphines, the reaction types, and the nature of the substrate. Because chiral phosphine-promoted Rauhut–Currier (RC) reactions [9][10] and MBH/aza-MBH reactions [21][22][23][24][25][26] have been