Reactions in multiindexed continuous mixtures: Catalytic cracking of petroleum fractions

Peixoto, Fernando Cunha; Medeiros, José Luiz de

doi:10.1002/aic.690470416

Cited by 24 publications

(18 citation statements)

References 32 publications

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“…Following Peixoto and de Medeiros (2001), it is employed, for g0(z), a Shulz-Zimm distribution, also known as Pearson type-III, which is an exponential distribution with two adjustable parameters (Abramowitz and Stegun, 1974) …”

Section: Modellingmentioning

confidence: 99%

Continuous modelling and kinetic parameter estimation for cellulose nitration

Barbosa

Merquior

Peixoto

2005

Chemical Engineering Science

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Section: Modellingmentioning

confidence: 99%

Continuous modelling and kinetic parameter estimation for cellulose nitration

Barbosa

Merquior

Peixoto

2005

Chemical Engineering Science

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“…The 12‐lump kinetic model for the FCC reactions used in this work is based on the work of Peixoto and Medeiros. 25 The detailed mechanism of the reactions and stoichiometry are discussed in Peixoto and Medeiros. 25 As seen in Table 1, the introduced scalar feed at the inlet cannot be considered as either non‐premixed or premixed due to the differences in the gas and the solid phase temperatures.…”

Section: Introductionmentioning

confidence: 99%

“…As discussed above the 12‐lump kinetic model proposed by Peixoto and Medeiros 25 is adopted in this work. The 12‐lump kinetic model is shown in Figure 6, while the rate coefficients and physical properties are summarised in Table 2.…”

Section: Introductionmentioning

confidence: 99%

Efficient Total Synthesis of Marine Alkaloid (−)‐Nakadomarin A

Cheng

Yang

et al. 2011

Chemistry A European J

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In 1997, Kobayashi and co-workers disclosed the isolation of (À)-nakadomarin A (1, Scheme 1) from an Okinawan marine sponge Amphimedon sp. Its unique 8/5/5/5/15/6 hexacyclic full-ring structure containing four stereogenic centers and an imbedded furan was shown with extensive NMR spectroscopic analyses including NOE and proton coupling data.[1a] The biological properties of 1 range from prominent cytotoxicity against murine lymphoma L1210 cells to outstanding antimicrobial and CDK4 inhibitory activities. [1b] Since 2003, elegant total and formal syntheses [2] of 1 have been accomplished by the laboratories of Nishida, [2a, b] Kerr, [2c] Dixon, [2d] Mukai, [2e] and Funk, [2f] and relevant synthesis studies have been reported by an array of research teams. [3] Having communicated a rapid construction of the tetracyclic core (ABCD rings) of ent-1 by showcasing the power of a Pt II -promoted cascade reaction sequence, [3i] we report herein a novel total synthesis of (À)-nakadomarin A with higher practicality and efficiency. The synthesis features: 1) the assembly of the tetracyclic core through the PtCl 2 -catalyzed cascade cyclization strategy [3i] (4!3, Scheme 1) followed by saturation [3i] of the C8=C9 double bond (3!2), and 2) CSA-assisted[2d] Z-selective olefin ringclosing metathesis (RCM; within 2!1) involving a monoamine precursor (17, Scheme 2) used to replace Dixons more polar diamine substrate (19 b) [2d] for the F ring generation. For the rest of our synthesis plan (Scheme 1), the E ring can be forged by typical olefin RCM [2a-c, e] (within 2! 1) prior to the F ring formation. Enyne 4 can be obtained through Sonogashira coupling of terminal alkyne 5 with iodofuran 7. While reductive amination of aldehyde 6 can be implemented to form alkyne 5, furan 7 can be accessible from cyclization/iodination of conjugated ynone 8 in the presence of hydriodic acid. Finally, ketone 8 can be prepared from 9 and 10.The synthesis of disubstituted furan 7 is described in Scheme 3. Propargyl alcohol THP ether [4] (9) was deprotonated and then treated with g-butyrolactone (10) in the presence of BF 3 ·OEt 2 to give ynone 8, treatment [5] of which with hydriodic acid (3 m) effected the desired cyclization/iodination to afford a mixture containing alcohol 11 and its THP ether (generated due to THP migration). Subjecting the above mixture to TsOH in MeOH led to 11 (52 %, from 9) as the sole product, which was silylated to furnish iodofuran 7 in 89 % yield.Unsaturated aldehyde 6[6] was converted into compound 5 (54 %, overall yield) by stepwise [3i] reductive amination (propargylamine . HCl, TEA, tBuOH, evaporation, NaBH 4 , MeOH) followed by N-sulfonylation (BsCl, TEA, DCM).[PdA C H T U N G T R E N N U N G (PPh 3 ) 2 Cl 2 ]/CuI-catalyzed Sonogashira coupling of terminal alkyne 5 with furan 7 in degassed TEA/DMF at room temperature gave rise to the key molecule 4 (87 %), in which the enecarbamate, alkyne and furan functionalities [7] By adopting our modified procedure, [3i] treatment of 4 (introduced to the r...

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“…1,2,8,9 Diffusion aspects required the calculation of the number of moles of nitronium ions available at each simulation time.…”

Section: Introductionmentioning

confidence: 99%