Pd- and Cu-catalyzed approaches in the syntheses of new cholane aminoanthraquinone pincer-like ligands

• Nikolay V. Lukashev,
• Gennadii A. Grabovyi,
• Dmitry A. Erzunov,
• Alexey V. Kazantsev,
• Gennadij V. Latyshev,
• Alexei D. Averin and
• Irina P. Beletskaya.

Beilstein J. Org. Chem. 2017, 13, 564–570, doi:10.3762/bjoc.13.55

• derivatives from various dibromo- and dichloroarenes [42]. Thus, we adopted the well performing Pd(dba)2/BINAP catalytic system for the reaction of aminocholanols 3a–c with dibromo- and dichloroarenes (Scheme 4). The synthesis of aniline 5a was chosen to determine the viability of Pd-catalyzed amination

• , the addition of an equimolar amount of iPrOH to the mixture of 3a and 6a under the same conditions led to the two-fold decrease in yield of 5c. The replacement of BINAP with other phosphine ligands (t-Bu3P, dppf, PPF-NMe2) gave a very low turnover of Pd catalyst (up to 8 cycles). The increase in

Facile synthesis of indolo[3,2-a]carbazoles via Pd-catalyzed twofold oxidative cyclization

• Chao Yang,
• Kai Lin,
• Lan Huang,
• Wei-dong Pan and
• Sheng Liu

Beilstein J. Org. Chem. 2016, 12, 2490–2494, doi:10.3762/bjoc.12.243

• dibromobenzoic acid with sulfuric acid in methanol) with an excess of anilines in the presence of cesium carbonate and catalytic quantities of Pd(OAc)2 and BINAP were processed smoothly. The desired methyl 2,4-dianilinobenzoates (2a–e) were obtained in good to excellent yield. In a parallel synthesis, using the

• materials. The operational simplicity combined with the convenience for introducing substituents to the aromatic rings makes this method useful. Natural indolo[3,2-a]carbazole alkaloids. Retrosynthetic analysis of indolo[3,2-a]carbazoles. Reagents and conditions: (a) H2SO4, MeOH; (b) Ar-NH2, Pd(OAc)2, BINAP

Stereo- and regioselectivity of the hetero-Diels–Alder reaction of nitroso derivatives with conjugated dienes

• Lucie Brulíková,
• Aidan Harrison,
• Marvin J. Miller and
• Jan Hlaváč

Beilstein J. Org. Chem. 2016, 12, 1949–1980, doi:10.3762/bjoc.12.184

• when the reaction was performed in the presence of Lewis acids [142]. In 2004, the Yamamoto group reported results from an asymmetric nitroso hetero-Diels–Alder reaction between 6-substituted nitrosopyridine 195 (where R1 = H) and 1,3-cyclohexadienes 196 using Cu(PF6)(MeCN)4-(S)-BINAP (198) as the

• catalyst (Scheme 39) [104]. The reaction was highly sensitive to the substituent R2 on the dienophile, with the methyl group giving the best stereoselectivity (87% relative to 56%, when R2 = H). After testing several BINAP-like catalysts, the reaction of the unsubstituted and monosubstituted 1,3

Stereodynamic tetrahydrobiisoindole “NU-BIPHEP(O)”s: functionalization, rotational barriers and non-covalent interactions

• Golo Storch,
• Sebastian Pallmann,
• Frank Rominger and
• Oliver Trapp

Beilstein J. Org. Chem. 2016, 12, 1453–1458, doi:10.3762/bjoc.12.141

• Axially chiral biaryl compounds such as BINAP (2,2’-bis(diphenylphosphino)-1,1’-binaphthyl) represent widely used and highly efficient ligands that can be applied in a variety of enantioselective catalytic transformations. Unlike BINAP, the related stereodynamic BIPHEP (2,2’-bis(diphenylphosphino)-1,1

• a key step in deracemization of stereodynamic compounds but they also allow ee determination in solution by NMR spectroscopy. However, the formation of diastereomeric adducts between chiral compounds and BIPHEP(O) [25] or BINAP(O) [26] has so far rarely been investigated. In a subsequent part of our

Conjugate addition–enantioselective protonation reactions

• James P. Phelan and
• Jonathan A. Ellman

Beilstein J. Org. Chem. 2016, 12, 1203–1228, doi:10.3762/bjoc.12.116

• this context, Reetz and co-workers were the first to report the transition metal-catalyzed enantioselective addition of arylboronic acids to an α-substituted-α,β-unsaturated ester to provide enantioenriched phenylalanine derivatives 48a (Scheme 10) [29]. Notably, a BINAP-derived rhodium(I) catalyst was

• itaconate (50) in the presence of a rhodium(I) catalyst and (R)-BINAP ligand (43, Figure 2) [31]. During optimization they found that switching to potassium organotrifluoroborates from organoboronic acids was necessary to achieve high enantioinduction. Additionally, the enantioselectivity was highly

• addition–enantioselective protonation to prepare esters with α,α-dibenzyl substitution [36]. The addition of arylboronic acids 47 to α-benzylacrylates 63 were catalyzed by a rhodium(I) (S)-BINAP (45, Figure 2) complex with boric acid as a proton source (Scheme 15). A variety of electron-rich, neutral, and

Chiral cyclopentadienylruthenium sulfoxide catalysts for asymmetric redox bicycloisomerization

• Barry M. Trost,
• Michael C. Ryan and
• Meera Rao

Beilstein J. Org. Chem. 2016, 12, 1136–1152, doi:10.3762/bjoc.12.110

• , indicating that the tethered sulfoxide complex is much more efficient at catalyzing redox bicycloisomerization (Table 4, entry 2). As one would expect from the lessons learned in the previous studies, chiral bidentate (R)-BINAP completely inhibits any reactivity (Table 4, entry 3). Surprisingly, monodentate

Catalytic asymmetric synthesis of biologically important 3-hydroxyoxindoles: an update

• Bin Yu,
• Hui Xing,
• De-Quan Yu and
• Hong-Min Liu

Beilstein J. Org. Chem. 2016, 12, 1000–1039, doi:10.3762/bjoc.12.98

• ligands were found to be important in determining the reactivity and enantioselctivity. When BINAP (L9) and the electron-rich ligand L10 were used, low yields and ee evalues were observed (data not shown here). Additonally, the title compouds can also be obtained in good yields (up to 95% yield) and with

Recent advances in metathesis-derived polymers containing transition metals in the side chain

• Ileana Dragutan,
• Valerian Dragutan,
• Bogdan C. Simionescu,
• Albert Demonceau and
• Helmut Fischer

Beilstein J. Org. Chem. 2015, 11, 2747–2762, doi:10.3762/bjoc.11.296

• novel immobilized Rh catalytic system in which the metal is embedded, by means of the 5,5-dinorimido BINAP ligand, into the polymer, obtained from alternating ROMP of cyclooctene with the Grubbs first generation catalyst, has been disclosed in a patent by Bergens et al. [63]. This catalytic system

Copper-catalyzed asymmetric conjugate addition of organometallic reagents to extended Michael acceptors

• Thibault E. Schmid,
• Sammy Drissi-Amraoui,
• Christophe Crévisy,
• Olivier Baslé and
• Marc Mauduit

Beilstein J. Org. Chem. 2015, 11, 2418–2434, doi:10.3762/bjoc.11.263

• (CuTC) and (R)-Binap L4, which afforded the desired final products bearing two stereogenic centers with excellent diastereoselectivies (93–97%). N-Heterocyclic carbenes (NHCs) have emerged, in these last two decades, as a powerful and versatile class of ligands, and appeared to be potent in many

• performance in terms of enantioselectivity, and was used in combination with Cu(OTf)2 in the 1,6-ACA of cyclic dienones of the type 30 (Scheme 6). NHC ligands also enabled a total regioselectivity and ees ranging from 58 to 91%. Given the efficiency of (R)-Binap L4 in Cu-catalyzed 1,4-ACA on α,β-unsaturated

• studied the reactivity of various β,γ-unsaturated α-ketoesters, which remain to date the only report dealing with such substrates in Cu-catalyzed ACA of trialkylaluminium [41]. Using the (R)-Binap-based system L4/CuTC, an excellent 1,4-selectivity was achieved with mono-unsaturated substrates. Dienic

Selected synthetic strategies to cyclophanes

• Sambasivarao Kotha,
• Mukesh E. Shirbhate and
• Gopalkrushna T. Waghule

Beilstein J. Org. Chem. 2015, 11, 1274–1331, doi:10.3762/bjoc.11.142

• provided acrylate 226, which was subjected to enantioselective copper-catalyzed conjugate addition with a methyl Grignard reagent involving (R)-tol-BINAP ligand to generate ester 227 in good yield and high enantiopurity. This intermediate was then converted to the key metathesis precursor involving a three

• -trimerization of two different alkynes with a high chemo- and regioselectivity. The Rh(I)/H8-BINAP complex catalyzed the partially intermolecular cyclotrimerization of 1,9-decadiyne (271) and diethyl acetylenedicarboxylate (272) to give [6]metacyclophane derivative 273 (Scheme 44) [177]. This approach is also

• applicable to synthesize various polyether-based cyclophanes. In this report, they have synthesized various polyether containing cyclophanes by a cross-cyclotrimerization catalyzed by a cationic rhodium(I)/H8-BINAP complex as a key step. The ether linked α,ω-diynes and dimethyl acetylenedicarboxylate were

An intramolecular C–N cross-coupling of β-enaminones: a simple and efficient way to precursors of some alkaloids of Galipea officinalis

• Hana Doušová,
• Radim Horák,
• Zdeňka Růžičková and
• Petr Šimůnek

Beilstein J. Org. Chem. 2015, 11, 884–892, doi:10.3762/bjoc.11.99

• with an increased amount of palladium, applied to 3e as the model substrate. However these conditions failed (Table 2, entry 1). Changing the ligand to DavePhos (L3) or BINAP (L5) (Figure 2) did not improve the situation at all (Table 2, entries 2 and 3). The application of a palladacycle-based pre

Diastereoselective and enantioselective conjugate addition reactions utilizing α,β-unsaturated amides and lactams

• Katherine M. Byrd

Beilstein J. Org. Chem. 2015, 11, 530–562, doi:10.3762/bjoc.11.60

• -unsaturated amides [143]. They were able to obtain high enantioselectivities using a catalyst generated from Rh(acac)(C2H4) and (S)-BINAP. Unfortunately, the 1,4-addition products were only obtained in moderate yields because of incomplete conversion of the starting material. This problem could be rectified

•  14 highlights an example of the rhodium-catalyzed asymmetric 1,4-addition of amides. In seminal reports for the rhodium-catalyzed ECA reactions, BINAP or a BINAP derivative was used as the chiral ligand for these reactions. Hayashi in 2003 [146] and Carreira in 2004 [147] demonstrated that chiral

• also able to apply the methodology to an α,β-unsaturated lactam (Scheme 18). Though Binap and bicyclic diene ligands have been highlighted in this section, several other ligands have been used in rhodium-catalyzed asymmetric 1,4-additions of α,β-unsaturated amides and lactams (Figure 5). Besides the

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

• , and generally display poor enantioselectivities for phosphine organocatalysis. For example, 2,2´-bis(diphenylphosphino)-1,1´-binaphthyl (BINAP) is an excellent chiral diphosphine ligand for metal-catalyzed asymmetric reactions, but it displays extremely poor reactivity and enantioselectivity in many

Rational design of cyclopropane-based chiral PHOX ligands for intermolecular asymmetric Heck reaction

• Marina Rubina,
• William M. Sherrill,
• Alexey Yu. Barkov and
• Michael Rubin

Beilstein J. Org. Chem. 2014, 10, 1536–1548, doi:10.3762/bjoc.10.158

• ; Introduction The asymmetric Heck reaction is one of the most powerful and versatile processes for the enantioselective construction of new carbon–carbon bonds. Intramolecular versions of this reaction catalysed by palladium complexes with BINAP and related diphosphine ligands [1][2] allow for efficient

• been made towards the application of BINAP-type ligands in the intermolecular asymmetric Heck reaction [15]. This reaction was pioneered by Hayashi [16], who demonstrated the arylation of dihydrofuran (1) with phenyl triflate (2a) (Scheme 1) in the presence of (R)-BINAP [16][17][18] produced isomeric

• enantioselectivity in the intramolecular Heck reaction. Several derivatives of BINAP [19][20] and other chiral diphosphines [21][22][23][24][25][26][27] including TMBTP [28][29][30][31], BIPHEP [32][33][34], BITIANP [30][35] (Figure 1) were tested, some of which provided improved selectivity. Nevertheless, in all

Preparation of phosphines through C–P bond formation

• Iris Wauters,
• Wouter Debrouwer and
• Christian V. Stevens

Beilstein J. Org. Chem. 2014, 10, 1064–1096, doi:10.3762/bjoc.10.106

• )-BINAP 116; a successful chiral ligand. Nickel was chosen as catalyst instead of palladium to minimize catalyst poisoning by binding of the metal with the phosphines present. After optimization, the desired chiral BINAP 116 was obtained in 77% yield. This protocol has been adopted by other research

Phosphinate-containing heterocycles: A mini-review

• Olivier Berger and
• Jean-Luc Montchamp

Beilstein J. Org. Chem. 2014, 10, 732–740, doi:10.3762/bjoc.10.67

• LiHMDS (Scheme 5) [19]. Tanaka and coworkers have synthesized chiral benzopyrano and naphthopyrano-fused helical phosphafluorenes 14a–d from dialkynyl phosphinate 12 and phenol-linked terminal tetrayne 13 at room temperature for only 1 h using a cationic rhodium(I)/(R)-tol-BINAP complex as a catalyst

Silver and gold-catalyzed multicomponent reactions

• Giorgio Abbiati and
• Elisabetta Rossi

Beilstein J. Org. Chem. 2014, 10, 481–513, doi:10.3762/bjoc.10.46

• tautomerization. Instead, an Ag(I) complex based on BINAP and AgSbF6 was employed as a catalyst for the enantioselective 1,3-dipolar cycloaddition reaction of azomethine ylides and alkenes for the synthesis of pyrrolidines 81 and 82 (Scheme 38) [97]. The reaction was developed mainly as a two-component reaction

• dealing with the use of BINAP–AgClO4 as a chiral catalyst in the same two-component reaction [98]. Higher enantioselectivities were rarely observed with SbF6− being the weaker coordinating counter ion. An interesting application of silver catalysis in the allene chemistry field has been recently proposed

Boron-substituted 1,3-dienes and heterodienes as key elements in multicomponent processes

• Ludovic Eberlin,
• Fabien Tripoteau,
• François Carreaux,
• Andrew Whiting and
• Bertrand Carboni

Beilstein J. Org. Chem. 2014, 10, 237–250, doi:10.3762/bjoc.10.19

• and co-workers described metal-catalysed tandem Diels–Alder/hydrolysis reactions of 2-boron-substituted 1,3-dienes [54][55]. Boron-dienes containing various ligands reacted with maleimides in the presence of rhodium and copper catalysts using BINAP as ligand (Scheme 15). NMR analysis of the crude

Recent advances in transition metal-catalyzed Csp²-monofluoro-, difluoro-, perfluoromethylation and trifluoromethylthiolation

• Grégory Landelle,
• Armen Panossian,
• Sergiy Pazenok,
• Jean-Pierre Vors and
• Frédéric R. Leroux

Beilstein J. Org. Chem. 2013, 9, 2476–2536, doi:10.3762/bjoc.9.287

• -catalyzed perfluoroalkylation of arenes in the absence of directing groups [70]. Perfluoroalkyl iodides were used as the source of the fluorinated alkyl group. Under the optimized reaction conditions, a mixture of the iodide, 5 mol % Pd2dba3, 20 mol % BINAP, cesium carbonate (2 equiv) and the arene (large

Synthetic scope and DFT analysis of the chiral binap–gold(I) complex-catalyzed 1,3-dipolar cycloaddition of azlactones with alkenes

• María Martín-Rodríguez,
• Luis M. Castelló,
• Carmen Nájera,
• José M. Sansano,
• Olatz Larrañaga,
• Abel de Cózar and
• Fernando P. Cossío

Beilstein J. Org. Chem. 2013, 9, 2422–2433, doi:10.3762/bjoc.9.280

• base (Figure 1) [18][19]. This catalytic system was very effective but the reactions performed with (R)-Binap(AuOBz)2 (Figure 1) as catalyst offered a very low enantioselection, for example, a 8% ee was achieved in the 1,3-DC of alanine derived azlactone and N-phenylmaleimide (NPM). Numerous gold

• efficient in asymmetric catalysis [23][24]. The high amount of gold per mole of catalyst and the chiral ligand itself make these processes somehow expensive. The relative lower cost of chiral privileged ligand Binap (versus Cy-Segphos) and the good results obtained in the 1,3-DC of α-imino esters and

• ) complexes 3 and 4, identified and characterized by Puddephatt’s group [X = trifluoroacetate (TFA)] [29][30][31], were obtained from NaAuCl4 and dimethyl sulfide and the corresponding amount of the chiral Binap ligand. Finally, the anion interchange was promoted by the addition of an equivalent amount of

An overview of the synthetic routes to the best selling drugs containing 6-membered heterocycles

• Marcus Baumann and
• Ian R. Baxendale

Beilstein J. Org. Chem. 2013, 9, 2265–2319, doi:10.3762/bjoc.9.265

• racemic quinuclidinol. However, an improved approach makes use of a Noyori-type asymmetric reduction employing a BINAP ligated RuCl2 and a chiral diamine to yield the desired (R)-quinuclidine in high yield and enantioselectivity [78]. The enantioselective synthesis of the tetrahydroisoquinoline fragment

Gold(I)-catalyzed enantioselective cycloaddition reactions

• Fernando López and
• José L. Mascareñas

Beilstein J. Org. Chem. 2013, 9, 2250–2264, doi:10.3762/bjoc.9.264

• , Xylyl-Binap(AuCl)2/AgSbF6 was more efficient, facilitating good yields of the corresponding products and enantioselectivities between 75 and 92%. In these cases, the bulky pivaloate at the propargylic position led to lower enantioselectivites than a less congested acetate group, showcasing that a fine

Palladium-catalyzed synthesis of N-arylated carbazoles using anilines and cyclic diaryliodonium salts

• Stefan Riedmüller and
• Boris J. Nachtsheim

Beilstein J. Org. Chem. 2013, 9, 1202–1209, doi:10.3762/bjoc.9.136

• the yield slightly decreases (Table 1, entry 11). We also tested t-Bu-Xantphos (Table 1, entry 8) as a common ligand with a higher bite angle. However, this Xantphos derivative is totally inefficient in our coupling reaction. Dppf and BINAP gave very similar results in isolated yield (natural bite

Recent advances in transition-metal-catalyzed intermolecular carbomagnesiation and carbozincation

• Kei Murakami and
• Hideki Yorimitsu

Beilstein J. Org. Chem. 2013, 9, 278–302, doi:10.3762/bjoc.9.34

• salt, (R)-tol-BINAP, and zinc triflate and subsequent quenching with benzoyl chloride afforded 3h in 75% yield with 93% ee. The addition of zinc triflate may help the formation of a more reactive cationic palladium(II) species. Under similar conditions, Lautens also reported palladium-catalyzed

Iridium-catalyzed intramolecular [4 + 2] cycloadditions of alkynyl halides

• Andrew Tigchelaar and
• William Tam

Beilstein J. Org. Chem. 2012, 8, 1765–1770, doi:10.3762/bjoc.8.201

• aromatized cycloadduct 6 (Table 1, entries 5–8). Using racemic BINAP and PPh3 ligands also provided 2 in low yield, but a significant amount of 6 was also formed. From these observations, [IrCl(cod)]2 (2 mol %) and dppe (4 mol %) were carried forward, and a variety of solvents were screened at different