73803-82-4

Upstream product

• 67-56-1 methanol 
• 96-37-7 methyl-cyclopentane 
• 41158-41-2 1-methyl-2-methylene-cyclopentane 
• 55536-08-8 ethyl p-aminophenyl acetate 
• 22911-33-7 1-(methoxycarbonyl)-2-methylcyclopentane 
• 124-63-0 methanesulfonyl chloride 
• 201230-82-2 carbon monoxide 
• 693-89-0 1-methylcyclopent-1-ene 
• 40911-84-0 dimethyl-2R,2S' dicyclopentyl-1R,1S' cetone 
• 20106-44-9 trans-2-Methylcyclopentanecarbaldehyde 
• 3070-53-9 1,6-heptadiene 
• 3664-70-8 trans-1-(2-methylcyclopentyl)ethanone 
• 4541-43-9 trans-2-methylcyclopentanecarboxylic acid 

Downstream Products

• 81328-62-3 (2-methylcyclopent-1-enyl)methanol 
• 822-50-4 trans-1,2-dimethylcyclopentane 
• 1192-18-3 cis-1,2-dimethylcyclopentane 

Relevant academic research and scientific papers

THE STEREOCHEMISTRY OF THE HYDROBORATION REARRANGEMENT

Hydroboration of 1,2-dimethylcyclopentene with BH3*THF affords a product in which boron migrates stereospecifically at low temperature into the cyclopentane ring.At higher temperatures subsequent (non-stereospecific) isomerisation occurs via a competing reaction mechanism.

Fe-Catalyzed Anaerobic Mukaiyama-Type Hydration of Alkenes using Nitroarenes

Hydration of alkenes using first row transition metals (Fe, Co, Mn) under oxygen atmosphere (Mukaiyama-type hydration) is highly practical for alkene functionalization in complex synthesis. Different hydration protocols have been developed, however, control of the stereoselectivity remains a challenge. Herein, highly diastereoselective Fe-catalyzed anaerobic Markovnikov-selective hydration of alkenes using nitroarenes as oxygenation reagents is reported. The nitro moiety is not well explored in radical chemistry and nitroarenes are known to suppress free radical processes. Our findings show the potential of cheap nitroarenes as oxygen donors in radical transformations. Secondary and tertiary alcohols were prepared with excellent Markovnikov-selectivity. The method features large functional group tolerance and is also applicable for late-stage chemical functionalization. The anaerobic protocol outperforms existing hydration methodology in terms of reaction efficiency and selectivity.

Ligand-Controlled Direct Hydroformylation of Trisubstituted Olefins

The direct hydroformylation of trisubstituted olefins has been achieved with a combination of a Rh(I) catalyst and a π-acceptor phosphorus (briphos) ligand. A sterically bulky briphos ligand with a large cone angle that forms a 1:1 complex with Rh(I) is found to be reactive for the hydroformylation of trisubstituted olefins. The aldehyde products were obtained with high diastereoselectivity (>99:1) and regioselectivity (49%-81%).

Radical addition of silanes to alkenes followed by oxidation

Phenyldimethylsilane and trichlorosilane are shown to undergo efficient radical hydrosilylation reactions, on reaction with various alkenes, using triethylborane as the initiator. Adducts from the trichlorosilane reactions can be oxidised to afford alcohols in good yields. This two-step process leads to the anti-Markovnikov hydration of alkenes. Georg Thieme Verlag Stuttgart · New York.

Selective generation of free radicals from epoxides using a transition-metal radical. A powerful new tool for organic synthesis

Bis(cyclopentadienyl)titanium(III) chloride reacts with epoxides by initial C-O homolysis. The regiochemistry of the opening is determined by the relative stabilities of the radicals. Depending on the reaction partners, these radicals undergo intramolecular (hex-5-enyl cyclization) or intermolecular additions to olefins. The resultant radicals are efficiently scavenged by a second equivalent of Ti(III) to afford the corresponding Ti(IV) derivative. Treatment of this intermediate with electrophiles such as H+ or halogens provides a route to functionalized cyclopentanes and other useful products. The radical initially formed from an epoxide can also be trapped by H-atom donors such as 1,4-cyclohexadiene or tert-butyl thiol, resulting in an overall reduction of the epoxide. In the absence of a H-atom donor or an olefin, this radical is trapped by Ti(III), resulting in a β-oxido-Ti organometallic species which undergoes facile elimination to give an olefin. The reaction conditions are remarkably mild and are applicable to very sensitive substrates.

Alkane Functionalization on a Preparative Scale by Mercury-Photosensitized Cross-Dehydrodimerization

Alkanes can be functionalized with high conversions and in high chemical and quantum yields on a multigram scale by mercury-photosensitized reaction between an alkane and alcohols, ethers, or silanes to give homodimers and cross-dehydrodimers.The separation of the product mixtures is often particulary easy because of a great difference in polarity of the homodimers and cross-dimers.It is also possible to bias the product composition when the ratio of the components in the vapor phase is adjusted by altering the liquid composition.This is useful either to maximize chemical yield or to ease separation by favoring the formation of the most easily separated pair of compounds.The mechanistic basis of the reaction is discussed and a number of specific types of syntheses, for example of 2,2-disubstituted carbinols, are described in detail.The selectivity of cross-dimerization is shown to exceed that for homodimerization and reasons are discussed.Relative reactivities of different compounds and classes of compound are MeOHp-dioxanecyclohexane1,3,5-trioxacyclohexaneethanolisobutaneTHFEt3SiH.The observed selectivities generally parallel those for homodimerization, reported in the preceding paper, but certain differences are noted, and reasons for the differences are proposed.The bond-dissociation energy of Et3SiH is estimated from the reactivity data to be 90 kcal/mol.Eleven new carbinols are synthesized.

Organoboranes. 41. Reaction of Organoboranes with (Dichloromethyl)lithium. Scope and Limitations. Synthesis of Homologated Primary and Secondary Alcohols

Homologated primary alcohols were prepared from alkylboronic esters by the reaction with (dichloromethyl)lithium, LiCHCl2, followed by KIPBH treatment and oxidation.Homologated secondary alcohols were prepared from representative dialkylborinic esters and trialkylboranes by the reaction with LiCHCl2, followed by treatment with base and oxidation.The yields are generally good with both boronic and borinic esters.On the other hand, the reactions with trialkylboranes exhibited a sensitivity to large steric requirements in the trialkylborane reactant.

ORGANOBORANES. 32. HOMOLOGATION OF ALKYLOBORONIC ESTERS WITH METHOXY(PHENYLTHIO)METHYLLITHIUM: REGIO- AND STEREOCONTROLLED ALDEHYDE SYNTHESIS FROM OLEFINS VIA HYDROBORATION.

Homologation of 2-alkyl-1,3,2-dioxaborinanes, RBO//2C//3H//6 (1), to alpha -methoxyalkyl derivatives, RCH(OMe) BO//2C//3H//6 (2), was achieved by reaction with LiCH(OMe) SPh, followed by treatment with HgCl//2. The intermediates 2 were smoothly oxidized with hydrogen peroxide in a pH 8 phosphate buffer to give the corresponding aldehydes, RCHO (3). The alkyl groups of 1 were introduced by the hydroboration method. Thus, heptanal, 3-phenylbutanal, 2-ethylpentanal, cyclohexanecarbaldehyde, trans-2-methylcyclopentanecarbaldehyde, and exo-norbornanecarbaldehyde were prepared in fair to good yields from 1-hexene, 2-phenylpropene, 3-hexene, cyclohexene, 1-methylcyclopentene, and norbornene, respectively. Furthermore, both threo- and erythro-2,-dimethylpentanal were obtained in 96% diastereomeric purity from (E)- and (Z)-3-methyl-2-pentene, respectively. The migration of the alkyl group from boron to carbon proceeds with retention of configuration.

4-[Cycloalkyl- or cycloalkenyl-amino(cycloalkyl- or cycloalkenyl-alkenyl)amino]phenyl compounds, useful as hypolipidemic and antiatherosclerotic agents

This disclosure describes novel 4-[(cycloalkyl or cycloalkenyl substituted)amino, alkylamino or alkenylamino]phenyl compounds, salts and derivatives of these such as cycloalkylamino, cycloalkenylamino, cycloalkyl-alkylamino, cycloalkyl-alkenylamino, cyclo