- Hydroformylation of 1,6-Dienes with Carbonylhydridotris(triphenylphosphine)rhodium
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Hydroformylation of a number of 1,6-dienes has been achieved at room temperature and atmospheric pressure using as catalyst.Octa-1,6-dienes are hydroformylated specifically at the terminal double bond and good selectivity for the n-aldehyde is observed when a 2:1 mixture of hydrogen and carbon monoxide are used.Both mono- and di-formyl derivatives are formed from 4,4-diacetylhepta-1,6-diene, with a strong preference for n-aldehydes.The effect of catalyst concentration on product distribution is reported.Octa-1,3,7-triene can be selectively hydroformylated by protecting the diene moiety as its cycloadduct with sulphur monoxide or dioxide, and whilst methylenecyclopentane undergoes regiospecific hydroformylation, methylenecyclobutane is isomerised to methylcyclobutene.
- Grigg, Ronald,Reimer, Gerald J.,Wade, Alan R.
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- ASPARAGINE DERIVATIVES AND METHODS OF USE THEREOF
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The present invention relates to compounds of formulas (A) and (I), pharmaceutically acceptable salts thereof, and solvates of any of them, pharmaceutical compositions comprising them, methods of preparation thereof, intermediate compounds useful for the preparation thereof, and methods of treatment or prophylaxis of diseases, in particular cancer, such as colorectal cancer, using these. (A) (I)
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Paragraph 00831-00832
(2021/12/31)
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- Iron-Catalyzed C-C Single-Bond Cleavage of Alcohols
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An iron-catalyzed deconstruction/hydrogenation reaction of alcohols through C-C bond cleavage is developed through photocatalysis, to produce ketones or aldehydes as the products. Tertiary, secondary, and primary alcohols bearing a wide range of substituents are suitable substrates. Complex natural alcohols can also perform the transformation selectively. A investigation of the mechanism reveals a procedure that involves chlorine radical improved O-H homolysis, with the assistance of 2,4,6-collidine.
- Liu, Wei,Wu, Qiang,Wang, Miao,Huang, Yahao,Hu, Peng
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supporting information
p. 8413 - 8418
(2021/11/01)
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- An Engineered Alcohol Oxidase for the Oxidation of Primary Alcohols
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Structure-guided directed evolution of choline oxidase has been carried out by using the oxidation of hexan-1-ol to hexanal as the target reaction. A six-amino-acid variant was identified with a 20-fold increased kcat compared to that of the wild-type enzyme. This variant enabled the oxidation of 10 mm hexanol to hexanal in less than 24 h with 100 % conversion. Furthermore, this variant showed a marked increase in thermostability with a corresponding increase in Tm of 20 °C. Improved solvent tolerance was demonstrated with organic solvents including ethyl acetate, heptane and cyclohexane, thereby enabling improved conversions to the aldehyde by up to 30 % above conversion for the solvent-free system. Despite the evolution of choline oxidase towards hexan-1-ol, this new variant also showed increased specific activities (by up to 100-fold) for around 50 primary aliphatic, unsaturated, branched, cyclic, benzylic and halogenated alcohols.
- Heath, Rachel S.,Birmingham, William R.,Thompson, Matthew P.,Taglieber, Andreas,Daviet, Laurent,Turner, Nicholas J.
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p. 276 - 281
(2019/01/04)
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- MODULATORS OF SESTRIN-GATOR2 INTERACTION AND USES THEREOF
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The present invention provides compounds, compositions thereof, and methods of using the same.
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Paragraph 00503; 00505; 00506
(2018/11/22)
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- α-Tetrasubstituted Aldehydes through Electronic and Strain-Controlled Branch-Selective Stereoselective Hydroformylation
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Hydroformylation utilizes dihydrogen, carbon monoxide, and a catalyst to transform alkenes into aldehydes. This work applies chiral bisdiazaphospholane (BDP)- and bisphospholanoethane-ligated rhodium complexes to the hydroformylation of a variety of alkenes to produce chiral tetrasubstituted aldehydes. 1,1′-Disubstituted acrylates bearing electron-withdrawing substituents undergo hydroformylation under mild conditions (1 mol % of catalyst/BDP ligand, 150 psig gas, 60 °C) with high conversions and yields of tetrasubstituted aldehydes (e.g., 13:1 regioselectivity, 85% ee, and 99% regioselectivity and >19:1 diastereoselectivity to tetrasubstituted aldehydes at rates >50 catalyst turnovers/hour. NMR studies of the noncatalytic reaction of HRh(BDP)(CO)2 with methyl 1-fluoroacrylate enable interception of tertiary alkylrhodium intermediates, demonstrating migratory insertion to acyl species is slower than formation of secondary and primary alkylrhodium intermediates. Overall, these investigations reveal how the interplay of sterics, electronics, and ring strain are harnessed to provide access to valuable α-tetrasubstituted aldehyde synthetic building blocks by promoting branched-selective hydroformylation.
- Eshon, Josephine,Foarta, Floriana,Landis, Clark R.,Schomaker, Jennifer M.
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p. 10207 - 10220
(2018/09/06)
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- MODULATORS OF SESTRIN-GATOR2 INTERACTION AND USES THEREOF
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The present invention provides compounds, compositions thereof, and methods of using the same.
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Paragraph 0591
(2017/05/15)
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- NRF2 REGULATORS
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Provided are aryl analogs,pharmaceutical compositions containing them and their use as NRF2 regulators.
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Page/Page column 368; 369
(2017/01/02)
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- NITROGEN-CONTAINING HETEROCYCLIC COMPOUND OR SALT THEREOF
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A compound represented by Formula [1] (in the formula, Z1 represents N, CH, or the like; X1 represents NH or the like; R1 represents a heteroaryl group or the like; each of R2, R3, and R4 represents a hydrogen atom, a halogen atom, an alkoxy group, or the like; and R5 represents a heteroaryl group or the like) or salt thereof.
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Paragraph 0913; 0914; 0915
(2015/11/30)
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- Catalytic, enantioselective, and highly chemoselective bromocyclization of olefinic dicarbonyl compounds
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Overriding preferences: An amine-thiocarbamate catalyst can mediate the facile, efficient, and highly enantioselective bromocyclization of olefinic 1,3-dicarbonyl compounds. In the presence of the bifunctional catalyst, the bromination occurs chemoselectively at the olefinic moiety rather than at the carbon atom in the α-position to the carbonyl units. Copyright
- Zhao, Yi,Jiang, Xiaojian,Yeung, Ying-Yeung
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supporting information
p. 8597 - 8601
(2013/09/12)
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- HETEROCYCLIC COMPOUNDS AS JANUS KINASE INHIBITORS
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The invention provides compounds of formula (I) or a salt thereof as described herein. The invention also provides pharmaceutical compositions comprising a compound of formula (I), processes for preparing compounds of formula (I), intermediates useful for preparing compounds of formula I and therapeutic methods for suppressing an immune response or treating cancer or a hematologic malignancy using compounds of formula (I).
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Page/Page column 161-162
(2011/04/18)
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- AZAINDOLE GLUCOKINASE ACTIVATORS
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Provided herein are compounds of the formula (I): as well as pharmaceutically acceptable salts thereof, wherein the substituents are as those disclosed in the specification. These compounds, and the pharmaceutical compositions containing them, are useful for the treatment of metabolic diseases and disorders such as, for example, type II diabetes mellitus.
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Page/Page column 13
(2011/06/26)
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- Expedient reductive animation of aldehyde bisulfite adducts
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A novel, one-pot protocol for the direct reductive animation of aldehyde bisulfite adducts is reported. Bisulfite adducts of aliphatic and aromatic aldehydes, on treatment with an organic base under non-aqueous conditions liberate the aldehyde in situ, which then undergoes efficient reductive amination with amines in the presence of sodium triacetoxyborohydride.
- Pandit, Chennagiri R.,Mani, Neelakandha S.
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experimental part
p. 4032 - 4036
(2010/03/24)
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- Rhodium-catalyzed hydroformylation of olefins: Effect of [bis(2,4-di-tert-butyl) pentaerythritol] diphosphite (alkanox P-24) on the regioselectivity of the reaction
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Rhodium (I) associated with [bis(2,4-di-tert-butyl) pentaerythritol] diphosphite (I) as a ligand represents an active catalyst system for highly regioselective hydroformylation of various alkenes. The commercially available bis(2,4-di-tert-butyl)pentaerythritol diphosphite (alkanox P-24) (I), which has been used so far as an antioxidant in the stabilization of polymers, was used as a diphosphite ligand for the selective hydroformylation reaction of olefins. Excellent selectivity towards linear aldehydes and excellent conversions were achieved in the hydroformylation of alkenes. The hydroformylation reaction was applied to various olefinic substrates including the internal alkenes.
- Tijani, Jimoh,El Ali, Bassam
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p. 3492 - 3497
(2008/02/12)
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- Mechanistic studies of olefin metathesis by ruthenium carbene complexes using electrospray ionization tandem mass spectrometry
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The olefin metathesis reaction of the Grubbs ruthenium carbene complexes has been investigated in the gas phase by electrospray ionization tandem mass spectrometry. Relative rates of reaction for substituted ruthenium benzylidenes and alkylidenes after removal of one phosphine ligand were interpreted with the aid of linear free energy analysis and kinetic isotope effects. The experimental observations are consistent with a reaction profile in which the metallacyclobutane structure is a transition state rather than an intermediate, although alternative explanations cannot be wholly ruled out. Electron withdrawal on the carbene moiety is found to accelerate the metathesis reaction when only the metathesis step itself is examined. Quantum chemical calculations at a variety of levels were performed to check for the consistency of the interpretation.
- Adlhart, Christian,Hinderling, Christian,Baumann, Harold,Chen, Peter
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p. 8204 - 8214
(2007/10/03)
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- SYNTHESIS OF dl-PENTALENOLACTONES E AND F.
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The methyl esters of ( plus or minus )-pentalenolactone E and F have been synthesized by a route based on the intramolecular insertion of an alpha -acylcarbene into an unactivated C-H bond to effect closure of the key fused delta -lactone ring system. Lactone reduction, deketalization, and selective acetalization of the derived lactol provided as a mixture of epimers.
- Cane,Thomas
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p. 5295 - 5303
(2007/10/12)
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- A CONVENIENT SYNTHESIS OF ALDEHYDES FROM 1,2-DIMETHOXYETHENYL LITHIUM AND TRIALKYLBORANES
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The reaction of ate-complexes formed from 1,2-dimethoxyethenyllithium and trialkylboranes, with BF3:Et2O followed by hydrolysis with hydrochloric acid gives the corresponding aldehydes in good yields.
- Koshino, Junji,Sugawara, Takahiro,Yogo, Toshinobu,Suzuki, Akira
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p. 1149 - 1152
(2007/10/02)
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