Renzo Ruzziconi - Academia.edu (original) (raw)
Papers by Renzo Ruzziconi
Journal of Organic Chemistry, Feb 1, 1980
... 827 Enrico Baciocchi,* Renzo Ruzziconi, and Giovanni V. Sebastiani Dipartimento di Chimica, U... more ... 827 Enrico Baciocchi,* Renzo Ruzziconi, and Giovanni V. Sebastiani Dipartimento di Chimica, Universitd di Perugia, Perugia, Italy Received June 13, 1979 ... Soc., Perkin Trans. 2 1974, 1886. (4) Alunni, S.; Baciocchi, E.; Perucci, P. J. Org. Chem. 1977,42, 205. ...
Journal of the American Chemical Society, Sep 1, 1983
(d) Addition of 3a to (2,4-dinitrophenyl)hydrazine in ethanol at room temperature led to 1-naphth... more (d) Addition of 3a to (2,4-dinitrophenyl)hydrazine in ethanol at room temperature led to 1-naphthoyl (2.4-dinitropheny1)hydrazide (5m): mp 275-278 OC dec; amide carbonyl absorption at 1640 cm-I; mass spectrum, m/e 352 (M+).31 In a separate experiment reaction of 3a (77 mg, 0.5 mm) occurred violently with (2,4-dinitrophenyl)hydrazine (99 mg, 0.5 mmol) in concentrated sulfuric acid to give, after the mixture was poured on ice, 1-naphthoic acid (50 mg, %a), mp 159-161 OC, identical with an authentic sample. Reaction of 3a with Methylenetripbenylphosphorane. tert-Butyllithium (1.5 equiv) in hexane was added to methyltriphenylphosphonium bromide (179 mg, 0.5 mmol) in tetrahydrofuran (10 mL) at 0 O C , and the mixture was warmed to-25 "C and stirred until homogeneous. When the solutions were cooled to-78 OC, 3a (77 mg, 0.5 mmol) in tetrahydrofuran (10 mL) was added by syringe and the mixture was stirred at-78 OC for 1 h and then slowly warmed to room temperature. TLC indicated that 2b was not present. Aqueous sodium hydroxide was added, and the mixture was refluxed 24 h, cooled, and poured into water/ethyl ether. The ethereal layer, on drying (MgSO,) and chromatography on silica gel (benzene as eluent), yielded 1-acetonaphthalene (SO; 15 mg, I%), identical with an authentic sample. All attempts to prepare 2b by reactions of 3a with methylenetriphenylphosphorane were unsuccessful. National Institutes of Health Grant C A 11 185 (1974-1978) and elaborated on National Science Foundation Grants CHE-77-0367 and CHE-80-19750. We should like to thank the National Institutes of Health and the National Science Foundation for support of this work.
014 IL [2.2)PARACICLOFANO: SINTESI DI NUOVI DERIVATI E LORO APPLICAZIONE IN SINTESI ASIMMETRICA A... more 014 IL [2.2)PARACICLOFANO: SINTESI DI NUOVI DERIVATI E LORO APPLICAZIONE IN SINTESI ASIMMETRICA Antonio Cipiciani, Francesco Fringuelli, Oriana Pìennatti, Renzo Ruzziconi Dipartimento di Chimica, Università di Perugia, via Elce di Sotto, 8- 06123 Perugia, Italia oriana@unipg.it Fin dalla sua prima apparizione con la sintesi di Farthing et al. e successivamente con la popolarità raggiunta con Cram et.al. il sistema del [2.2]paraciclofano ha sempre avuto considerevole attenzione da parte dei chimici soprattutto per il suo inusuale sistema elettronico te distorto. Solo negli ultimi anni con lo sviluppo di nuove tecniche e metodologie la chimica del [22]paraciclofàno ha subito un nuovo inpulso con la sintesi di nuovi derivati e il loro utilizzo sia come ausiliari che come ligandi a chiralità planare in reazioni asimmetriche. Il nostro gruppo di ricerca da alcuni anni si sta interessando alla chimica del [2.2]paraciclofano. 1 Recentemente è stato preparato il (+)-R-[2.2]paraciclofano[4,5-d]- I ,3- oxaz.ol-2(3H)-one che è stato poi utilizzato con successo come ausiliare a chiralità planare nella condensazione aldolica via boro-enolato di acil e propionil-oxazoloni con la benzaldeide (ee 71 e 90% rispettivamente), nella reazione di Dìels-Alder di acriloil e crotonil-oxazoloni con il cìclopentadiene (endo/exo 2:98:2, endo-selettività facciale 86:14 e 98:2 rispettivamente) e nella addizione di Michael del crotonil-oxazolone con il fenilcuprato (ee2:99%).2 E stato inoltre preparato un nuovo ligando di tipo N,O: il (+)-R and (-)-S-4-metil-2- idrossimetil[2Jparaciclo[2](5,8)chinolinofano che è stato poi utilizzato nell'addizione stereoselettiva del dietil zinco ad una serie di aldeidi (ee 30- 75%).3 In questa comunicazione verranno presentati i risultati più recenti di questa ricerca. I. (a) Cipiciani, A.; FringueUi, F.; Mancini, V.; Piennatti, O.; Pizzo, F.; Ruzziconi, R. J. Org. Chem. 1997, 62, 3744-3447. (b) Cipiciani, A.; Fringuelli, F.; Mancini, V.; Picnnatti, O.; Scappini, M.; Ruzziconi, R. Tetrahedron 1997, 53, 11853-11858. 2. (a) Fringuelli, F.; Piennatti, O.; Pizzo, F.; Ruzziconi, R. Chemistry Lett. 2000, 38-39. (b) Cipiciani, A.; Fringuelli, F.; Piermatti, O.; Pizzo, F.; Ruzziconi, R. J. Org. Chem. 2002, in stampa. 3. Ruzziconi, R.; Piermatti, O.; Ricci, G.; Vinci, D. Synlett,2000, in stampa.
![Research paper thumbnail of ChemInform Abstract: (S)-(-)- and (R)-(+)-4-Methyl-2-hydroxymethyl[2]paracyclo-[2](5,8)quinolinophane: Novel N,O-Planar Chiral Catalysts for the Enantioselective Addition Diethylzinc to Aldehydes](https://attachments.academia-assets.com/113971860/thumbnails/1.jpg)
](
Synlett, Dec 31, 2001
ABSTRACT
![Research paper thumbnail of A Facile Access to Polycyclic Homo- and Heteroaromatic Hydrocarbons Based on the Ceric Ammonium Nitrate-Promoted Oxidative Addition of 3-Aryl-1-[(trimethylsilyl)oxy]cyclohexenes to Ethyl Vinyl Ether](https://attachments.academia-assets.com/113971857/thumbnails/1.jpg)
](Journal of Organic Chemistry, Apr 1, 1999
Journal of Medicinal Chemistry, May 9, 2014
r a 2 0 1 4. O p ti miz a tio n of s m all-m ol e c ul e in hi bi to r s of influ e n z a vir u s... more r a 2 0 1 4. O p ti miz a tio n of s m all-m ol e c ul e in hi bi to r s of influ e n z a vir u s p oly m e r a s e : F r o m t hio p h e n e-3-c a r b ox a mi d e t o p oly a mi d o s c affol d s. Jou r n al of M e dici n al C h e mi s t ry 5 7 (1 0) , p p.
ChemInform, Aug 22, 2010
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was e... more ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform, Aug 19, 2010
Review: 116 refs.
![Research paper thumbnail of ([2]Paracyclo[2](5,8)quinolinophan-2-yl)carbinols as Catalysts for Diethylzinc Addition to Aldehydes: Cooperative Effects of Planar and Central Chirality on the Asymmetric Induction](https://attachments.academia-assets.com/113971852/thumbnails/1.jpg)
](ChemInform, Oct 4, 2005
A systematic study to assess the contribution of planar and central chirality to the asymmetric i... more A systematic study to assess the contribution of planar and central chirality to the asymmetric induction in the diethylzinc addition to aromatic and aliphatic aldehydes has been carried out using planar chiral quinolinophanylcarbinols (R p)-1 and (R p)-11 and diastereomeric quinolinophanylcarbinols (R p ,R)-and (R p ,S)-5-8, exhibiting both planar and central chirality as catalysts. The stereochemistry of the addition process leading to aryl-or 1-alkylpropanols seems to be mostly controlled by the central chirality. Nevertheless, the planar chirality shows a remarkable cooperative effect on the degree of asymmetric induction, which turns out to be positive or negative depending on the configuration of the stereogenic carbon of the catalyst.
Chemistry: A European Journal, Sep 12, 2019
Journal of Organic Chemistry, Jun 1, 1978
A suspension of 18.3 g (0.15 mol) of potassium tert-butoxide in 200 mL of THF was cooled with ice... more A suspension of 18.3 g (0.15 mol) of potassium tert-butoxide in 200 mL of THF was cooled with ice-salt. Carbon dioxide was passed into the suspension with vigorous stirring for 30 min. A solution of 39.0 g (0.15 mol) of 2,4,5-trichlorophenyl chloroformate in 120 mL of THF was added dropwise. The reaction mixture was stirred at 0 O C for 2 h and 5-10 "C for another 1-5 h. Insoluble materials were removed, and the filtrate was evaporated at reduced pressure. The crude product was recrystallized from 400 mL of pentane and then from 280 mL of pentane to give 21.1 g (41%) of tert-butyl 2,4,5-trichlorophenyl dicarbonate, mp 65.5-66.5 "C. The IR spectrum (C Q) showed carbonyl bands at 1835 and 1770 cm-', and the NMR spectrum (CCld) showed peaks at 1.62 (s, 9L7.66
ChemPhotoChem, Dec 13, 2021
Journal of Molecular Catalysis B-enzymatic, Nov 1, 2006
ABSTRACT Lipases from Candida rugosa, Candida antartica B and Carica papaya are employed as the b... more ABSTRACT Lipases from Candida rugosa, Candida antartica B and Carica papaya are employed as the biocatalyst for the hydrolytic resolution of methyl 2-fluoro-2-arylpropionates in water-saturated isooctane, in which excellent to good enantioselectivity without the formation of byproducts is obtained for the papaya lipase when using (R,S)-2-fluoronaproxen methyl ester (1) and methyl (R,S)-2-fluoro-2-(4-methoxyphenyl)propionate (2), but not methyl (R,S)-2-fluoro-2-(naphth-1-yl)propionate (3) as the substrates. The thermodynamic analysis indicates that the enantiomer discrimination for the papaya lipase is driven by the difference in activation enthalpy for compound 1, 2 or (R,S)-naproxen methyl ester (4). The kinetic analysis also demonstrates that in comparison with (S)-4, the insertion of the 2-fluorine moiety in (R)-1 has increased k2, but not Km, and consequently the lipase activity.
Journal of Organic Chemistry, Aug 1, 1982
ABSTRACT
Organic and Biomolecular Chemistry, 2018
Journal of Organic Chemistry, Feb 1, 1980
... 827 Enrico Baciocchi,* Renzo Ruzziconi, and Giovanni V. Sebastiani Dipartimento di Chimica, U... more ... 827 Enrico Baciocchi,* Renzo Ruzziconi, and Giovanni V. Sebastiani Dipartimento di Chimica, Universitd di Perugia, Perugia, Italy Received June 13, 1979 ... Soc., Perkin Trans. 2 1974, 1886. (4) Alunni, S.; Baciocchi, E.; Perucci, P. J. Org. Chem. 1977,42, 205. ...
Journal of the American Chemical Society, Sep 1, 1983
(d) Addition of 3a to (2,4-dinitrophenyl)hydrazine in ethanol at room temperature led to 1-naphth... more (d) Addition of 3a to (2,4-dinitrophenyl)hydrazine in ethanol at room temperature led to 1-naphthoyl (2.4-dinitropheny1)hydrazide (5m): mp 275-278 OC dec; amide carbonyl absorption at 1640 cm-I; mass spectrum, m/e 352 (M+).31 In a separate experiment reaction of 3a (77 mg, 0.5 mm) occurred violently with (2,4-dinitrophenyl)hydrazine (99 mg, 0.5 mmol) in concentrated sulfuric acid to give, after the mixture was poured on ice, 1-naphthoic acid (50 mg, %a), mp 159-161 OC, identical with an authentic sample. Reaction of 3a with Methylenetripbenylphosphorane. tert-Butyllithium (1.5 equiv) in hexane was added to methyltriphenylphosphonium bromide (179 mg, 0.5 mmol) in tetrahydrofuran (10 mL) at 0 O C , and the mixture was warmed to-25 "C and stirred until homogeneous. When the solutions were cooled to-78 OC, 3a (77 mg, 0.5 mmol) in tetrahydrofuran (10 mL) was added by syringe and the mixture was stirred at-78 OC for 1 h and then slowly warmed to room temperature. TLC indicated that 2b was not present. Aqueous sodium hydroxide was added, and the mixture was refluxed 24 h, cooled, and poured into water/ethyl ether. The ethereal layer, on drying (MgSO,) and chromatography on silica gel (benzene as eluent), yielded 1-acetonaphthalene (SO; 15 mg, I%), identical with an authentic sample. All attempts to prepare 2b by reactions of 3a with methylenetriphenylphosphorane were unsuccessful. National Institutes of Health Grant C A 11 185 (1974-1978) and elaborated on National Science Foundation Grants CHE-77-0367 and CHE-80-19750. We should like to thank the National Institutes of Health and the National Science Foundation for support of this work.
014 IL [2.2)PARACICLOFANO: SINTESI DI NUOVI DERIVATI E LORO APPLICAZIONE IN SINTESI ASIMMETRICA A... more 014 IL [2.2)PARACICLOFANO: SINTESI DI NUOVI DERIVATI E LORO APPLICAZIONE IN SINTESI ASIMMETRICA Antonio Cipiciani, Francesco Fringuelli, Oriana Pìennatti, Renzo Ruzziconi Dipartimento di Chimica, Università di Perugia, via Elce di Sotto, 8- 06123 Perugia, Italia oriana@unipg.it Fin dalla sua prima apparizione con la sintesi di Farthing et al. e successivamente con la popolarità raggiunta con Cram et.al. il sistema del [2.2]paraciclofano ha sempre avuto considerevole attenzione da parte dei chimici soprattutto per il suo inusuale sistema elettronico te distorto. Solo negli ultimi anni con lo sviluppo di nuove tecniche e metodologie la chimica del [22]paraciclofàno ha subito un nuovo inpulso con la sintesi di nuovi derivati e il loro utilizzo sia come ausiliari che come ligandi a chiralità planare in reazioni asimmetriche. Il nostro gruppo di ricerca da alcuni anni si sta interessando alla chimica del [2.2]paraciclofano. 1 Recentemente è stato preparato il (+)-R-[2.2]paraciclofano[4,5-d]- I ,3- oxaz.ol-2(3H)-one che è stato poi utilizzato con successo come ausiliare a chiralità planare nella condensazione aldolica via boro-enolato di acil e propionil-oxazoloni con la benzaldeide (ee 71 e 90% rispettivamente), nella reazione di Dìels-Alder di acriloil e crotonil-oxazoloni con il cìclopentadiene (endo/exo 2:98:2, endo-selettività facciale 86:14 e 98:2 rispettivamente) e nella addizione di Michael del crotonil-oxazolone con il fenilcuprato (ee2:99%).2 E stato inoltre preparato un nuovo ligando di tipo N,O: il (+)-R and (-)-S-4-metil-2- idrossimetil[2Jparaciclo[2](5,8)chinolinofano che è stato poi utilizzato nell'addizione stereoselettiva del dietil zinco ad una serie di aldeidi (ee 30- 75%).3 In questa comunicazione verranno presentati i risultati più recenti di questa ricerca. I. (a) Cipiciani, A.; FringueUi, F.; Mancini, V.; Piennatti, O.; Pizzo, F.; Ruzziconi, R. J. Org. Chem. 1997, 62, 3744-3447. (b) Cipiciani, A.; Fringuelli, F.; Mancini, V.; Picnnatti, O.; Scappini, M.; Ruzziconi, R. Tetrahedron 1997, 53, 11853-11858. 2. (a) Fringuelli, F.; Piennatti, O.; Pizzo, F.; Ruzziconi, R. Chemistry Lett. 2000, 38-39. (b) Cipiciani, A.; Fringuelli, F.; Piermatti, O.; Pizzo, F.; Ruzziconi, R. J. Org. Chem. 2002, in stampa. 3. Ruzziconi, R.; Piermatti, O.; Ricci, G.; Vinci, D. Synlett,2000, in stampa.
Synlett, Dec 31, 2001
ABSTRACT
Journal of Organic Chemistry, Apr 1, 1999
Journal of Medicinal Chemistry, May 9, 2014
r a 2 0 1 4. O p ti miz a tio n of s m all-m ol e c ul e in hi bi to r s of influ e n z a vir u s... more r a 2 0 1 4. O p ti miz a tio n of s m all-m ol e c ul e in hi bi to r s of influ e n z a vir u s p oly m e r a s e : F r o m t hio p h e n e-3-c a r b ox a mi d e t o p oly a mi d o s c affol d s. Jou r n al of M e dici n al C h e mi s t ry 5 7 (1 0) , p p.
ChemInform, Aug 22, 2010
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was e... more ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform, Aug 19, 2010
Review: 116 refs.
ChemInform, Oct 4, 2005
A systematic study to assess the contribution of planar and central chirality to the asymmetric i... more A systematic study to assess the contribution of planar and central chirality to the asymmetric induction in the diethylzinc addition to aromatic and aliphatic aldehydes has been carried out using planar chiral quinolinophanylcarbinols (R p)-1 and (R p)-11 and diastereomeric quinolinophanylcarbinols (R p ,R)-and (R p ,S)-5-8, exhibiting both planar and central chirality as catalysts. The stereochemistry of the addition process leading to aryl-or 1-alkylpropanols seems to be mostly controlled by the central chirality. Nevertheless, the planar chirality shows a remarkable cooperative effect on the degree of asymmetric induction, which turns out to be positive or negative depending on the configuration of the stereogenic carbon of the catalyst.
Chemistry: A European Journal, Sep 12, 2019
Journal of Organic Chemistry, Jun 1, 1978
A suspension of 18.3 g (0.15 mol) of potassium tert-butoxide in 200 mL of THF was cooled with ice... more A suspension of 18.3 g (0.15 mol) of potassium tert-butoxide in 200 mL of THF was cooled with ice-salt. Carbon dioxide was passed into the suspension with vigorous stirring for 30 min. A solution of 39.0 g (0.15 mol) of 2,4,5-trichlorophenyl chloroformate in 120 mL of THF was added dropwise. The reaction mixture was stirred at 0 O C for 2 h and 5-10 "C for another 1-5 h. Insoluble materials were removed, and the filtrate was evaporated at reduced pressure. The crude product was recrystallized from 400 mL of pentane and then from 280 mL of pentane to give 21.1 g (41%) of tert-butyl 2,4,5-trichlorophenyl dicarbonate, mp 65.5-66.5 "C. The IR spectrum (C Q) showed carbonyl bands at 1835 and 1770 cm-', and the NMR spectrum (CCld) showed peaks at 1.62 (s, 9L7.66
ChemPhotoChem, Dec 13, 2021
Journal of Molecular Catalysis B-enzymatic, Nov 1, 2006
ABSTRACT Lipases from Candida rugosa, Candida antartica B and Carica papaya are employed as the b... more ABSTRACT Lipases from Candida rugosa, Candida antartica B and Carica papaya are employed as the biocatalyst for the hydrolytic resolution of methyl 2-fluoro-2-arylpropionates in water-saturated isooctane, in which excellent to good enantioselectivity without the formation of byproducts is obtained for the papaya lipase when using (R,S)-2-fluoronaproxen methyl ester (1) and methyl (R,S)-2-fluoro-2-(4-methoxyphenyl)propionate (2), but not methyl (R,S)-2-fluoro-2-(naphth-1-yl)propionate (3) as the substrates. The thermodynamic analysis indicates that the enantiomer discrimination for the papaya lipase is driven by the difference in activation enthalpy for compound 1, 2 or (R,S)-naproxen methyl ester (4). The kinetic analysis also demonstrates that in comparison with (S)-4, the insertion of the 2-fluorine moiety in (R)-1 has increased k2, but not Km, and consequently the lipase activity.
Journal of Organic Chemistry, Aug 1, 1982
ABSTRACT
Organic and Biomolecular Chemistry, 2018