Synthesis of SF₅-containing benzisoxazoles, quinolines, and quinazolines by the Davis reaction of nitro-(pentafluorosulfanyl)benzenes

• Petr Beier and
• Tereza Pastýříková

Beilstein J. Org. Chem. 2013, 9, 411–416, doi:10.3762/bjoc.9.43

• [26] nucleophiles, and oxidative nucleophilic substitution of hydrogen (ONSH) with Grignard and organolithium reagents [27]. This chemistry significantly expanded the range of available SF5-benzene derivatives. The synthetic chemistry and biological activity of pentafluorosulfanyl organic molecules

Inter- and intramolecular enantioselective carbolithiation reactions

• Asier Gómez-SanJuan,
• Nuria Sotomayor and
• Esther Lete

Beilstein J. Org. Chem. 2013, 9, 313–322, doi:10.3762/bjoc.9.36

• the possibility of introducing further functionalization on the molecule by trapping the reactive organolithium intermediates with electrophiles. Keywords: alkenes; asymmetric synthesis; carbolithiation; carbometallation; enantioselectivity; lithium; Introduction The carbolithiation reaction has

• attracted considerable interest among synthetic organic chemists, as it offers an attractive pathway for the efficient construction of new carbon–carbon bonds by addition of an organolithium reagent to nonactivated alkenes or alkynes, with the possibility of introducing further functionalization on the

• molecule by trapping the reactive organolithium intermediates with electrophiles. Several reviews have covered the synthetic applications of this kind of reaction [1][2][3][4][5][6][7][8]. When alkenes are used, up to two contiguous stereogenic centers may be generated, which may be controlled by using

Polar reactions of acyclic conjugated bisallenes

• Reiner Stamm and
• Henning Hopf

Beilstein J. Org. Chem. 2013, 9, 36–48, doi:10.3762/bjoc.9.5

• involving polar intermediates and/or transition states has been investigated on a broad scale for the first time. The reactions studied include lithiation, reaction of the thus formed organolithium salts with various electrophiles (among others, allyl bromide, DMF and acetone), oxidation to cyclopentenones

• Scheme 6 all of these experiments failed. Neither could we prepare the “coupling product” 27 by treatment of 4 with the biselectrophile dimethylysilyl dichloride nor the dimer 28 by the direct action of iodine on the organolithium compound 4. In this latter case we noted after work-up and GC–MS analysis

Intramolecular carbolithiation of N-allyl-ynamides: an efficient entry to 1,4-dihydropyridines and pyridines – application to a formal synthesis of sarizotan

• Wafa Gati,
• Mohamed M. Rammah,
• Mohamed B. Rammah and
• Gwilherm Evano

Beilstein J. Org. Chem. 2012, 8, 2214–2222, doi:10.3762/bjoc.8.250

• formal synthesis of the anti-dyskinesia agent sarizotan, further extends the use of ynamides in organic synthesis and further demonstrates the synthetic efficiency of carbometallation reactions. Keywords: carbolithiation; carbometallation; dihydropyridines; organolithium reagents; pyridines; sarizotan

The chemistry of bisallenes

• Henning Hopf and
• Georgios Markopoulos

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

• the tetramethylbutadiene 22 is first dibromocyclopropanated to the tetrabromide 23, which, on treatment with an organolithium reagent, is debrominated/rearranged to the target hydrocarbon 24. Hydrocarbon 24 is a stable colorless solid that can be worked with under normal laboratory conditions without

Alkenes from β-lithiooxyphosphonium ylides generated by trapping α-lithiated terminal epoxides with triphenylphosphine

• David. M. Hodgson and
• Rosanne S. D. Persaud

Beilstein J. Org. Chem. 2012, 8, 1896–1900, doi:10.3762/bjoc.8.219

• Cy3P did not lead to the orange–red colouration suggestive of ylide formation, and only starting epoxide 11 was observed. We also studied the possibility of generating alcohol 7 from terminal epoxide 11 using an organolithium instead of a hindered lithium amide as the base (Scheme 5). Organolithiums

• , in particular secondary and tertiary organolithiums, are known to react with terminal epoxides by α-lithiation, although this is typically followed by trapping of the α-lithiated epoxide with a second equivalent of the organolithium and elimination of Li2O to give an E-alkene (e.g., 12): a process

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

• accessible DTBAD through the organolithium. Although we focus on long-chain-substituted phenylhydrazines, we believe that this method can be used for other electron-rich arylhydrazines. Experimental Reagents and solvents were obtained commercially. Reactions were carried out under Ar. 1H NMR spectra were

Directed aromatic functionalization in natural-product synthesis: Fredericamycin A, nothapodytine B, and topopyrones B and D

• Charles Dylan Turner and
• Marco A. Ciufolini

Beilstein J. Org. Chem. 2011, 7, 1475–1485, doi:10.3762/bjoc.7.171

• ; nothapodytine; organolithium compounds; topopyrone; Review Our laboratory is primarily interested in the total synthesis of natural products, and does not conduct research on directed aromatic functionalization ("DAF") per se. On numerous occasions, however, DAF technology has been key to the success of

• through the union of fragments 56 or 57 with aldehyde 58: The carrier of a moiety that is common to all topopyrones. A serviceable form of 58 proved to be compound 65, the preparation of which is outlined in Scheme 12. A key step in this sequence was the addition of the organolithium species 60, obtained

• benzamide 56 with sec-BuLi/TMEDA (1.05 equiv, 3 h, −78 °C) and addition of the resulting organolithium agent to 65 was presumed to form the alkoxide 66. In situ treatment of 66 with t-BuLi induced bromine–lithium exchange and cyclization of organolithium species 67 to a product that was believed to be 68

Carbamate-directed benzylic lithiation for the diastereo- and enantioselective synthesis of diaryl ether atropisomers

• Abigail Page and
• Jonathan Clayden

Beilstein J. Org. Chem. 2011, 7, 1327–1333, doi:10.3762/bjoc.7.156

• organolithium compounds having varying degrees of configurational stability [17][18], and in our studies on ureas and amides we were able to identify correlated inversion processes linking configurational inversion at organolithium centres with conformational inversion of atropisomeric chirality by bond

• of the resulting organolithium returned the product 7 in up to 88% yield as a mixture of diastereoisomers (by NMR). Previous data on the conformational stability of related diaryl ether [10], coupled with our inability to separate these diastereoisomers, and the invariant ratio in which they were

• which the minor organolithium is rapidly converted to product, followed slowly by the major organolithium [28]. Hoppe observed a related effect in the alkylations of cinnamyllithiums [29]. Previous results from the laboratories of Hoppe indicated that lithiated O-benzylcarbamates are typically

Directed ortho,ortho'-dimetalation of hydrobenzoin: Rapid access to hydrobenzoin derivatives useful for asymmetric synthesis

• Inhee Cho,
• Labros Meimetis,
• Lee Belding,
• Michael J. Katz,
• Travis Dudding and
• Robert Britton

Beilstein J. Org. Chem. 2011, 7, 1315–1322, doi:10.3762/bjoc.7.154

• addition of organolithium reagents to arene tricarbonylchromium complexes [7] and α,β-unsaturated aldimines [8]. Notably, derivatives of hydrobenzoin in which the aromatic rings have been functionalized in the ortho and ortho' positions often display improved diastereo- or enantioselectivity over the

• reaction conditions [23]. Notably, addition of TMEDA (entries 3 and 5), which would presumably assist in the disaggregation of organolithium species, failed to improve these results and in fact led to lower conversion and isolated yields of the diiodohydrobenzoin 12. During the evaluation of the reaction

Bromine–lithium exchange: An efficient tool in the modular construction of biaryl ligands

• Laurence Bonnafoux,
• Frédéric R. Leroux and
• Françoise Colobert

Beilstein J. Org. Chem. 2011, 7, 1278–1287, doi:10.3762/bjoc.7.148

• ). Results and Discussion Regioselective bromine–lithium exchange on polybrominated biphenyls Our group recently reported the efficient coupling of organolithium intermediates with arynes, the so-called "ARYNE coupling" [25][31][36]. This protocol is based on the formation of a thermodynamically stable

Meta-metallation of N,N-dimethylaniline: Contrasting direct sodium-mediated zincation with indirect sodiation-dialkylzinc co-complexation

• David R. Armstrong,
• Liam Balloch,
• Eva Hevia,
• Alan R. Kennedy,
• Robert E. Mulvey,
• Charles T. O'Hara and
• Stuart D. Robertson

Beilstein J. Org. Chem. 2011, 7, 1234–1248, doi:10.3762/bjoc.7.144

• capable of selectively abstracting hydrogen from organic substrates continues. Routinely, organolithium reagents have been employed for this purpose with the high electropositivity of lithium affording polar, reactive Cδ−–Liδ+ bonds proficient in metallating C–H bonds in organic, especially aromatic and

Selectivity in C-alkylation of dianions of protected 6-methyluridine

• Ngoc Hoa Nguyen,
• Christophe Len,
• Anne-Sophie Castanet and
• Jacques Mortier

Beilstein J. Org. Chem. 2011, 7, 1228–1233, doi:10.3762/bjoc.7.143

• Li2CuCl4 [16][17][18] to 11 followed by quenching with 4-bromobut-1-ene failed to produce 3a. Consequently, lateral lithiations were examined. Lateral lithiation of benzenoid aromatics requires a stabilizing group capable of either delocalizing negative charge or stabilizing an organolithium by

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

• inter- or intramolecularly [8][9][10][11][12][13][14][15][16]. However, an increased range of aromatic moieties can be introduced through the use of organometallic compounds. The most commonly employed reagents are organoindium [17][18], organolithium [19][20], organomagnesium [21][22], organotin [23

When cyclopropenes meet gold catalysts

• Frédéric Miege,
• Christophe Meyer and
• Janine Cossy

Beilstein J. Org. Chem. 2011, 7, 717–734, doi:10.3762/bjoc.7.82

• , allylic ethers derived from cyclopropenyl carbinols were selected as substrates. Cyclopropenyl carbinols have recently emerged as synthetically useful building blocks [39] and are readily available by the condensation of an in situ generated cyclopropenyl organolithium with an aldehyde [39][40

Asymmetric synthesis of tertiary thiols and thioethers

• Jonathan Clayden and
• Paul MacLellan

Beilstein J. Org. Chem. 2011, 7, 582–595, doi:10.3762/bjoc.7.68

• medicinal chemistry, surprisingly few effective methods are suitable for the asymmetric synthesis of tertiary thiols. This review details the most practical of the methods available. Keywords: asymmetric synthesis; organolithium; sulfur; substitution; thiol; Introduction Organosulfur compounds play key

• )-thiolactomycin (66) in >99:1 er. 2.2 Electrophilic attack on α-thioorganolithiums Formation of carbon–carbon bonds adjacent to heteroatoms by deprotonation with an organolithium base and subsequent reaction with an electrophile has become an important and versatile method, especially when chiral ligands may be

• presence of (−)-sparteine 74 (Scheme 26) were attempted [64]. Trapping the lithiated intermediate 75 with electrophiles gave products with poor enantioselectivities, but the results gave no indication of the configurational stability of the intermediate organolithium 75. To establish the factors governing

α,β-Aziridinylphosphonates by lithium amide-induced phosphonyl migration from nitrogen to carbon in terminal aziridines

• David. M. Hodgson and
• Zhaoqing Xu

Beilstein J. Org. Chem. 2010, 6, 978–983, doi:10.3762/bjoc.6.110

• substrate 1a (57%, Scheme 4) [28]. Initially, we examined organolithiums for their propensity to induce deprotonation-migration in N-phosphonate aziridine 1a. Despite it being previously noted by Zwierzak that the reaction of organolithium reagents with such substrates resulted in preferential attack at

Aromatic and heterocyclic perfluoroalkyl sulfides. Methods of preparation

• Vladimir N. Boiko

Beilstein J. Org. Chem. 2010, 6, 880–921, doi:10.3762/bjoc.6.88

• behavior in their reactions with nucleophiles. For example, the reaction of CF3I with alkali gives fluoroform (CHF3) and potassium hypoiodide (KIO) [122]. The interaction of organolithium compounds with perfluoroalkyl iodides [123][124][125][126] does not result in combination of the two alkyl species (RF

Synthesis of unsymmetrically substituted biaryls via sequential lithiation of dibromobiaryls using integrated microflow systems

• Aiichiro Nagaki,
• Naofumi Takabayashi,
• Yutaka Tomida and
• Jun-ichi Yoshida

Beilstein J. Org. Chem. 2009, 5, No. 16, doi:10.3762/bjoc.5.16

• temperatures such as 0 °C. It is also noteworthy that monolithiation of 2,2′-dibromobibenzyl (43) can be achieved with high selectivity even at 0 °C and 24 °C. The resulting organolithium intermediate reacted with various electrophiles to give the corresponding products in high yields with high selectivity

Recent progress on the total synthesis of acetogenins from Annonaceae

• Nianguang Li,
• Zhihao Shi,
• Yuping Tang,
• Jianwei Chen and
• Xiang Li

Beilstein J. Org. Chem. 2008, 4, No. 48, doi:10.3762/bjoc.4.48

Allylsilanes in the synthesis of three to seven membered rings: the silylcuprate strategy

• Asunción Barbero,
• Francisco J. Pulido and
• M. Carmen Sañudo

Beilstein J. Org. Chem. 2007, 3, No. 16, doi:10.1186/1860-5397-3-16

• before (see Scheme 3), gives chemoselectively methylenecyclopentanols, while the vinylsilane unit remains unchanged (Scheme 10). [24] Recent work revealed that addition one equivalent of organolithium reagent (R1Li) to the reaction mixture leads to the formation of ketones of type 46 (Scheme 10), which

Pd-catalysed [3 + 3] annelations in the stereoselective synthesis of indolizidines

• Olivier Y. Provoost,
• Andrew J. Hazelwood and
• Joseph P. A. Harrity

Beilstein J. Org. Chem. 2007, 3, No. 8, doi:10.1186/1860-5397-3-8

• the absence of the alkyllithium reagent. As outlined in Table 1, Entries 2–4, the annelation was found to proceed in the absence of n-BuLi, however, in all cases the yield of cyclisation product was significantly lower than with catalyst generated by the organolithium reagent. Whilst the underlying

An efficient synthesis of novel pyrano[2,3-d]- and furopyrano[2,3-d]pyrimidines via indium- catalyzed multi- component domino reaction

• Dipak Prajapati and
• Mukut Gohain

Beilstein J. Org. Chem. 2006, 2, No. 11, doi:10.1186/1860-5397-2-11

• %). Introduction The emergence of indium(III) compounds as efficient Lewis acid catalysts presents new and exciting opportunities for organoindium chemistry. [1][2] It was found that the low reactivity of trivalent organoindium reagents can be increased by complex formation with organolithium compounds.[3] The

An exceptional P-H phosphonite: Biphenyl- 2,2'-bisfenchylchlorophosphite and derived ligands (BIFOPs) in enantioselective copper- catalyzed 1,4-additions

• T. Kop-Weiershausen,
• J. Lex,
• J.-M. Neudörfl and
• B. Goldfuss

Beilstein J. Org. Chem. 2005, 1, No. 6, doi:10.1186/1860-5397-1-6

• recently applied in chiral organolithium reagents [52][53][54][55][56][57][58] and in organozinc [59][60][61][62] as well as in organopalladium catalysts [63][64][65][66][67] to study origins of enantioselectivities in C-C-couplings. The rigid, terpene-based bicyclo[2.2.1]heptane unit enables efficient