Cu-catalyzed trifluoromethylation of aryl iodides with trifluoromethylzinc reagent prepared in situ from trifluoromethyl iodide

• Yuzo Nakamura,
• Motohiro Fujiu,
• Tatsuya Murase,
• Yoshimitsu Itoh,
• Hiroki Serizawa,
• Kohsuke Aikawa and
• Koichi Mikami

Beilstein J. Org. Chem. 2013, 9, 2404–2409, doi:10.3762/bjoc.9.277

• organometallic reagents such as lithium and magnesium, which are widely utilized in non-fluorine organic synthesis, cannot be used. These trifluoromethyl metal reagents are generally too unstable to prepare even at low temperature because of facile α-fluoro elimination generating the singlet difluoromethylene

A protecting group-free synthesis of the Colorado potato beetle pheromone

• Zhongtao Wu,
• Manuel Jäger,
• Jeffrey Buter and
• Adriaan J. Minnaard

Beilstein J. Org. Chem. 2013, 9, 2374–2377, doi:10.3762/bjoc.9.273

• , oxidation and stereoselective methylation using organometallic reagents are the key steps, affording (S)-1 in high enantiomeric purity and in gram quantities. In all these approaches, however, protection of the primary hydroxy group of the 1,2,3-triol substructure is required for the selective oxidation of

Homolytic substitution at phosphorus for C–P bond formation in organic synthesis

• Hideki Yorimitsu

Beilstein J. Org. Chem. 2013, 9, 1269–1277, doi:10.3762/bjoc.9.143

• reactions such as nucleophilic substitution of P–X compounds with organometallic reagents, nucleophilic substitution of alkyl halides with phosphorus nucleophiles, and nucleophilic addition to polar unsaturated bonds. Recent advances in transition-metal catalysis have realized catalytic cross-coupling

Preparation and ring-opening reactions of N-diphenylphosphinyl vinyl aziridines

• Ashley N. Jarvis,
• Andrew B. McLaren,
• Helen M. I. Osborn and
• Joseph Sweeney

Beilstein J. Org. Chem. 2013, 9, 852–859, doi:10.3762/bjoc.9.98

• established and optimized the method for the preparation of N-Dpp vinyl aziridines, we next turned to an examination of their reactions with a range of nucleophiles, first considering reactions with organometallic reagents. Thus N-Dpp vinyl aziridines 1, 2 and 4 reacted with lithio dialkylcuprates with

• mixture. Aza-Darzens synthesis of an N-Dpp vinyl aziridine. Closed transition state delivers E-aziridines. Open transition state leading to (Z)-5. Ring opening by Grignard reagent. Aza-Darzens synthesis of N-Dpp vinyl aziridines. SN2′-Ring-opening of N-Dpp vinyl aziridines by organometallic reagents. Ring

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

• metal; Introduction Whereas direct transformations of unreactive carbon–hydrogen or carbon–carbon bonds have been attracting increasing attention from organic chemists, classical organometallic reagents still play indispensable roles in modern organic chemistry. Among the organometallic reagents

The chemistry of bisallenes

• Henning Hopf and
• Georgios Markopoulos

Beilstein J. Org. Chem. 2012, 8, 1936–1998, doi:10.3762/bjoc.8.225

• highly substituted allenes; it is summarized in compact form in Scheme 4. By this approach the substituted allene derivatives 33 or the propargyl derivatives 34 are coupled with organometallic reagents 35 in the presence of a Pd-catalyst to the different allenes and bisallenes 36. The yields are normally

Synthesis of a library of tricyclic azepinoisoindolinones

• Bettina Miller,
• Shuli Mao,
• Kara M. George Rosenker,
• Joshua G. Pierce and
• Peter Wipf

Beilstein J. Org. Chem. 2012, 8, 1091–1097, doi:10.3762/bjoc.8.120

• synthetic building blocks, a variety of approaches for the preparation of these heterocycles have been explored [11][12][13][14][15][16][17][18]. Previously, we reported on the addition of organometallic reagents to in situ generated N-acyliminium ions [19]. This methodology applies to a variety of

Carbohydrate-auxiliary assisted preparation of enantiopure 1,2-oxazine derivatives and aminopolyols

• Marcin Jasiński,
• Dieter Lentz and
• Hans-Ulrich Reissig

Beilstein J. Org. Chem. 2012, 8, 662–674, doi:10.3762/bjoc.8.74

• addition of an excess of organometallic reagents furnishing compounds of type C (Nu1 = Nu2) was described and discussed by Goti et al. (Scheme 1) [32]. In selected examples, the synthesis of differently substituted products (Nu1 ≠ Nu2) was possible by consecutive additions of the appropriate Grignard

Branching out at C-2 of septanosides. Synthesis of 2-deoxy-2-C-alkyl/aryl septanosides from a bromo-oxepine

• Supriya Dey and
• Narayanaswamy Jayaraman

Beilstein J. Org. Chem. 2012, 8, 522–527, doi:10.3762/bjoc.8.59

• -alkyl/aryl derivatives, through C–C bond formations mediated by organometallic reagents. Details of the preparation of 2-deoxy-2-C-aryl/alkyl septanosides are described herein. Results and Discussion The methodology of septanoside preparation starting from an oxyglycal is shown in Figure 1 [21]. The

Synthesis of oleophilic electron-rich phenylhydrazines

• Aleksandra Jankowiak and
• Piotr Kaszyński

Beilstein J. Org. Chem. 2012, 8, 275–282, doi:10.3762/bjoc.8.29

• deprotection of hydrazides II have been developed (Figure 1). Hydrazides II are efficiently obtained by the addition of organometallic reagents III, prepared from aryl halide IV, to azodicarboxylate diesters (AD) [16][17]. Alternatively, II can be obtained in the Pd(0)- or Cu2+-catalyzed reaction of

Synthetic approaches to multifunctional indenes

• Neus Mesquida,
• Sara López-Pérez,
• Immaculada Dinarès and
• Ermitas Alcalde

Beilstein J. Org. Chem. 2011, 7, 1739–1744, doi:10.3762/bjoc.7.204

• ; amides; indanones; indenes; organometallic reagents; Introduction Compounds with an indene core are of great interest as precursors of metallocene complexes for catalytic polymerization processes, as well as being present in N-heterocyclic carbene ligands and functional materials [1][2][3][4][5][6][7][8

Functionalization of heterocyclic compounds using polyfunctional magnesium and zinc reagents

• Paul Knochel,
• Matthias A. Schade,
• Sebastian Bernhardt,
• Georg Manolikakes,
• Albrecht Metzger,
• Fabian M. Piller,
• Christoph J. Rohbogner and
• Marc Mosrin

Beilstein J. Org. Chem. 2011, 7, 1261–1277, doi:10.3762/bjoc.7.147

• has been shown to be of radical nature, and it affords the cross-coupling products in very short reaction times, often less than 5 min. 4 MgCl2-Enhanced reactivity of functionalized organozincs towards their addition to aldehydes, ketones and carbon dioxide The addition reactions of organometallic

• reagents to ketones, aldehydes and carbon dioxide are essential transformations in organic synthesis as they provide a convenient access to various types of alcohols or carboxylic acids. Usually, organozinc reagents only react with these types of electrophiles in the presence of catalytic amounts of

A practical route to tertiary diarylmethylamides or -carbamates from imines, organozinc reagents and acyl chlorides or chloroformates

• Erwan Le Gall,
• Antoine Pignon and
• Thierry Martens

Beilstein J. Org. Chem. 2011, 7, 997–1002, doi:10.3762/bjoc.7.112

• methods differ notably. Indeed, while the synthesis of secondary N-protected diarylmethylamines generally relies on the addition of organometallic reagents to electron-deficient (activated) imines [3][4][5][6][7], the preparation of tertiary diarylmethylamides or -carbamates may be conducted through the

• group has been involved in various projects pertaining to the development of multicomponent reactions (MCRs) involving organometallic reagents, in particular organozinc reagents, due to their ability to react in very mild conditions and generally preserve most common functional groups. Moreover, used in

Metathesis access to monocyclic iminocyclitol-based therapeutic agents

• Ileana Dragutan,
• Valerian Dragutan,
• Carmen Mitan,
• Hermanus C.M. Vosloo,
• Lionel Delaude and
• Albert Demonceau

Beilstein J. Org. Chem. 2011, 7, 699–716, doi:10.3762/bjoc.7.81

• 69 provides an attractive starting point since it reacts with organometallic reagents with a high degree of diastereoselectivity and minimal racemization. N-allylation (allyl iodide/NaH; 95% yield) of an intermediate derived from 70 gave the diolefin product 71, which was then subjected to RCM

Recent advances in carbocupration of α-heterosubstituted alkynes

• Ahmad Basheer and
• Ilan Marek

Beilstein J. Org. Chem. 2010, 6, No. 77, doi:10.3762/bjoc.6.77

• obtained at −10 °C but a mixture was formed with the anti adduct as the major product at room temperature. When R2 = t-Bu, anti addition was observed exclusively. Fluorinated alkynylphosphonates 30 can also be carbometalated with various organometallic reagents as summarized in Scheme 15 [33]. When RCuCNLi

Continuous flow enantioselective arylation of aldehydes with ArZnEt using triarylboroxins as the ultimate source of aryl groups

• Julien Rolland,
• Xacobe C. Cambeiro,
• Carles Rodríguez-Escrich and
• Miquel A. Pericàs

Beilstein J. Org. Chem. 2009, 5, No. 56, doi:10.3762/bjoc.5.56

• transferred to the reacting carbonyl compound. It is to be mentioned that other strategies for the preparation of mixed alkylarylzinc species from cheap organometallic reagents have been developed in recent times and could probably be also used for the same purpose [33][34][35]. Flow chemistry [36][37][38][39

A stable enol from a 6-substituted benzanthrone and its unexpected behaviour under acidic conditions

• Marc Debeaux,
• Kai Brandhorst,
• Peter G. Jones,
• Henning Hopf,
• Jörg Grunenberg,
• Wolfgang Kowalsky and
• Hans-Hermann Johannes

Beilstein J. Org. Chem. 2009, 5, No. 31, doi:10.3762/bjoc.5.31

• derivatives have been shown to be efficient emitters for OLED applications [2]. In these devices, the benzanthrone moiety acts as an electron accepting group, whereas the diarylamine group functions as an electron donor. The reaction of 1 with various organometallic reagents was studied by Allen in the 1970s

Trifluoromethyl ethers – synthesis and properties of an unusual substituent

• Frédéric R. Leroux,
• Baptiste Manteau,
• Jean-Pierre Vors and
• Sergiy Pazenok

Beilstein J. Org. Chem. 2008, 4, No. 13, doi:10.3762/bjoc.4.13

• the trifluoromethoxy group by 0.5 – 1.0 units [60][61][62]. Reactivity The OCF3 group is thermally and chemically resistant to attack by acids, bases, organometallic reagents and oxidizing/reducing agents [23][36]. When substituted on an aromatic ring, the trifluoromethoxy group exhibits similar

Mechanistic aspects of the isomerization of Z-vinylic tellurides double bonds in the synthesis of potassium Z-vinyltrifluoroborate salts

• Hélio A. Stefani,
• Rafael C. Guadagnin,
• Artur F. Keppler,
• Giancarlo V. Botteselle,
• João V. Comasseto and
• Carlos A. Suganuma

Beilstein J. Org. Chem. 2008, 4, No. 9, doi:10.1186/1860-5397-4-9

• reactions with several different commonly used, commercially available, or easily prepared organometallic reagents, leading to Z-vinyllithiums and Z-vinylcyanocuprates. In reactions promoted by Pd or Ni, these compounds undergo stereospecific coupling with a wide range of organic species [8]. The vinylic

Analogues of amphibian alkaloids: total synthesis of (5R,8S,8aS)-(−)-8-methyl- 5-pentyloctahydroindolizine (8-epi-indolizidine 209B) and [(1S,4R,9aS)-(−)-4-pentyloctahydro- 2H-quinolizin- 1-yl]methanol

• Joseph P. Michael,
• Claudia Accone,
• Charles B. de Koning and
• Christiaan W. van der Westhuyzen

Beilstein J. Org. Chem. 2008, 4, No. 5, doi:10.1186/1860-5397-4-5

• by a leaving group that can be displaced by organometallic reagents (e.g. cuprates) of appropriate chain length. Substituents at C-4 can also be varied by choosing appropriate analogues of the chiral amine 14, which should also be available in both enantiomeric forms by the Davies procedure [32

Synthesis of densely functionalized enantiopure indolizidines by ring- closing metathesis (RCM) of hydroxylamines from carbohydrate- derived nitrones

• Marco Bonanni,
• Marco Marradi,
• Francesca Cardona,
• Stefano Cicchi and
• Andrea Goti

Beilstein J. Org. Chem. 2007, 3, No. 44, doi:10.1186/1860-5397-3-44

• the addition of organometallic reagents. [21][22] Recently, we developed a general protocol for the synthesis of α,α'-disubstituted enantiopure hydroxylamines 1 through the stereoselective double addition of an excess of a Grignard reagent to C-phenyl-N-erythrosylnitrone 2 (Scheme 1).[23] With this

Expedient syntheses of the N-heterocyclic carbene precursor imidazolium salts IPr·HCl, IMes·HCl and IXy·HCl

• Lukas Hintermann

Beilstein J. Org. Chem. 2007, 3, No. 22, doi:10.1186/1860-5397-3-22

• pyrophoric organometallic reagents, and they are conveniently stored and used in the form of their air-stable precursors, namely the imidazolium salts IPr·HCl (1,3-bis-{2,6-diisopropylphenyl}imidazolium chloride; 1) or IMes·HCl (1,3-bis-{2,4,6-trimethylphenyl}imidazolium chloride; 2) (Figure 1). At present