62985-48-2

Upstream product

• 4685-74-9 <8>paracyclophane 
• 62985-49-3 3-methylenespiro<5.7>trideca-1,4-diene 
• 62985-47-1 3-methylenespiro<5.6>undeca-1,4-diene 
• 28785-06-0 4-n-propylbenzaldehyde 
• 1779-49-3 Methyltriphenylphosphonium bromide 
• 62452-73-7 1-ethynyl-4-propylbenzene 
• 588-93-2 p-bromo-n-propylbenzene 
• 79-10-7 acrylic acid 
• 52315-65-8 spiro<5.6>trideca-1,4-dien-3-one 
• 3761-63-5 <7>paracyclophane 
• 116059-93-9 dispiro<2.2.6.2>tetradeca-4,13-diene 

Relevant academic research and scientific papers

In-situ facile synthesis novel N-doped thin graphene layer encapsulated Pd@N/C catalyst for semi-hydrogenation of alkynes

Transition metal-catalyzed semi-hydrogenation of alkynes has become one of the most popular methods for alkene synthesis. Specifically, the noble metal Pd, Rh, and Ru-based heterogeneous catalysts have been widely studied and utilized in both academia and industry. But the supported noble metal catalysts are generally suffering from leaching or aggregation during harsh reaction conditions, which resulting low catalytic reactivity and stability. Herein, we reported the facile synthesis of nitrogen doped graphene encapsulated Pd catalyst and its application in the chemo-selective semi-hydrogenation of alkynes. The graphene layer served as “bulletproof” over the active Pd Nano metal species, which was confirmed by X-ray and TEM analysis, enhanced the catalytic stability during the reaction conditions. The optimized prepared Pd@N/C catalyst showed excellent efficiency in semi-hydrogenation of phenylacetylene and other types of alkynes with un-functionalized or functionalized substituents, including the hydrogenation sensitive functional groups (NO2, ester, and halogen).

Discovery of Novel Sphingosine-1-Phosphate-1 Receptor Agonists for the Treatment of Multiple Sclerosis

The sphingosine-1-phosphate-1 (S1P1) receptor agonists have great potential for the treatment of multiple sclerosis (MS) because they can inhibit lymphocyte egress through receptor internalization. We designed and synthesized triazole and isoxazoline derivatives to discover a novel S1P1agonist for MS treatment. Of the two scaffolds, the isoxazoline derivative was determined to have excellent in vitro efficacy and drug-like properties. Among them, compound 21l was found to have superior drug-like properties as well as excellent in vitro efficacies (EC50= 7.03 nM in β-arrestin recruitment and EC50= 11.8 nM in internalization). We also confirmed that 21l effectively inhibited lymphocyte egress in the peripheral lymphocyte count test and significantly improved the clinical score in the experimental autoimmune encephalitis MS mouse model.

Pd-Catalyzed Synthesis of Vinyl Arenes from Aryl Halides and Acrylic Acid

Acrylic acid is presented as an inexpensive, non-volatile vinylating agent in a palladium-catalyzed decarboxylative vinylation of aryl halides. The reaction proceeds through a Heck reaction of acrylic acid, immediately followed by protodecarboxylation of the cinnamic acid intermediate. The use of the carboxylate group as a deciduous directing group ensures high selectivity for monoarylated products. The vinylation process is generally applicable to diversely substituted substrates. Its utility is shown by the synthesis of drug-like molecules and the gram-scale preparation of key intermediates in drug synthesis.

FLASH VACUUM THERMOLYSIS OF DISPIROALKADIENES

The Flash Vacuum Thermolysis (FVT) of dispirotetradeca -4,13-diene (7a). dispirotrideca-4,12-diene (7b) and dispirodeca-4,9-diene (7e) at 500-750 deg C is reported.The complicated reaction mixture from 7a and 7b (Scheme 3) included at lower temperatures vinylspiroalkadienes 9, ethylidenespiroalkadiene 10b, β-ethylcycloalkabenzenes 11, while at higher temperatures, p-n-alkyl-(5) and p-sec-alkylstyrenes 14 and p-divinylbenzene (15) dominated.Product formation is explained by invoking diradicals 8,6 and 12 as well as the cyclophanes 1 and 13 as intermediates.For 7e, the product mixture was less complicated and consisted of p-ethylstyrene (5e), 15 and, unexpectedly,p-isopropylstyrene (14e) which contains one carbon more than the starting material.The analysis and interpretation of product formation largely confirms previously suggested reaction pathways and furnishes further interesting details.However, new and unexpected features are also encountered, especially in the fragmentations of 1 and 13 which may stimulate future investigations on the thermal behaviour of these relatively simple hydrocarbons.

SCOPE AND LIMITATIONS OF THE FLASH VACUUM THERMOLYSIS APPROACH TO SMALL PARACYCLOPHANES

Flash vacuum thermolysis (FVT) of 3-methylene-6-spirocyclohexa-1,4-dienes (2) was investigated as a synthetic approach to small paracyclophanes 1 (1a, n=8; 1b, n=7; 1c, n=6).The method was found to be preparatively attractive for 1a (80percent yield), less so for 1b (7percent useful yield), and not at all for 1c which was too unstable to survive the conditions of its formation.Besides 1, p-alkylstyrenes (3) and 2-methylbenzocycloalkenes (4) were obtained; the total recovery of monomeric products was good (60-85percent).The temperature dependence of product formation furnished useful information on the mechanisms of formation and decomposition of 1 under the conditions of FVT.

A comparative investigation of 1,4-pentamethylene and 1,4-hexamethylene Dewar benzene. Evidence for the intermediate formation of paracyclophane

The synthesis of the title compounds 1a and 1b is described.Starting from the corresponding 1,2-dimethylenecycloalkanes 6, the compounds 1 were obtained in four steps, viz. addition of dichlorocarbene, reduction with triphenyltin hydride, treatemnt with potassium tert-butoxide and silver-ion-catalyzed rearrangement.In the last step, the 1,2-isomers 11 of 1 were also formed, and their thermal rearrangement to the benzocycloalkenes 4 is briefly described.Compound 1b rearranged to its aromatic isomer (6)paracyclophane (2b) both thermally (60 deg C in solution, 100-460 deg C flow pyrolysis) and under silver-ion catalysis at room temperature; in this latter reaction the initially formed 2b was gradually further isomerized to 4b.At higher temperatures, 2b rearranged to the spirotrienes 3b and finally fragmented to give p-ethylstyrene (17).From 1a, the spirotriene 3a and benzocycloheptene (4a) were obtained by thermolysis and by silver-ion catalysis, respectively.The mechanism of these reactions is discussed and it is concluded that (5)paracyclophane (2a) is a transient intermediate in th reaction of 1a.