• Korean Chemical Engineering Research
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• 제53권4호
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• pp.463-467
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• 2015

We investigated catalytic activity of ion-exchange resins in acetalization of 1,2-propylene glycol with acetaldehyde. The impacts of reaction variables, such as temperature, reaction time, catalyst loading and feedstock composition, on the conversion of 1,2-propylene glycol were measured. The life of the catalyst was also studied. Furthermore, the reaction kinetics of 1,2-propylene glycol acetalization was studied. It was found that reaction rate followed the first-order kinetics to acetaldehyde and 1,2-propylene glycol, respectively. Therefore, overall acetalization reaction should follow the second-order reaction kinetics, expressed as. Key words: 1,2-propylene Glycol, 2,4-dimethyl-1,3-dioxolane, Ion-exchange Resin, Polyhydroxy Compounds, Acetalization $r=kC^{nA}_AC^{nB}_B=19.74e^{\frac{-6650}{T}}C^1_AC^1_B$.

• Bulletin of the Korean Chemical Society
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• 제9권6호
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• pp.379-381
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• 1988

Racemic nuciferal(1) and nuciferol(2), the terpenic natural perfumeries, have been synthesized by a simple procedure. The benzylic halide 6; 1-(1-chloroethyl)-4-methylbenzene, was prepared by converting p-tolualdehyde(4) into 1-(p-tolyl)-1-ethanol(5), followed by convertion of 5 into corresponding chloride. The Grignard reagent of 6 was reacted with the bromoacetal 7, 2-(2-bromoethyl)-1,3-dioxolane, to give a crosscoupling product 8, which was hydrolysed to 4-(p-tolyl)-pentanal (9). The Wittig reaction of isopropylide 10 with 9 yielded arcurcumen(11). The stereospecific allylic oxidation of the gem-dimethyl olefin 11 with selenium dioxide afforded a trans-aldehyde, (${\pm}$)-1, which was reduced to corresponding alcohol, (${\pm}$)-2.

• 한국결정학회지
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• 제11권1호
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• pp.22-27
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• 2000

The structure of cis-(malonato)[(4R,5R)-4,5-bis(aminomethyl)-2-isopropyl-1,3-dioxolane]platinum(II) with a potent anticancer activity has been determined by the X-ray crystallographic method. Crystal data are as follows: Pt(C/sub 11/H/sub 20/N₂O/sub 6/), M/sub 4/=471.38, monoclinic, P2₁, a=7.112(1), b=33.615(3), c=7.135(1)Å, β=116.80(1)°, V=1522.6(3)Å, and Z=4. The two independent molecules with very similar structures are approximately related by pseudo two-fold screw axis symmetry, which makes the monolinic cell look like the orthorhombic cell with one molecule in the asymmetric unit and space group C222₁. The crystal packing mode is similar to that of the analogue with the dimethyl substituents instead of the isopropyl group. The Pt atom is coordinate to two O and two N atoms in a square planar structure. The six-membered chelate ring in the leaving ligand assumes a conformation intermediate between the half chair and the boat forms. The seven-membered ring in the carrier ligand assumes a twist-chair conformation and the oxolane ring assumes an envelope conformation. Crystal packing consists of the extensive hydrogen-bonding network in the two-dimensional molecular layers and weak van der Waals interactions between these layers.

• Bulletin of the Korean Chemical Society
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• 제32권2호
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• pp.411-416
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• 2011

Steric and electronic parameters of 4'-substituents play significant roles in steering the conformation of nucleoside analogues. In order to investigate the relationship of 4'-group with antiviral enhancement, novel 4'-hydroxymethyl-5'-norcarbocyclic adenosine phosphonic acid analogues were designed and synthesized from 2,2-dimethyl-1,3-dioxolane-4-ethanol (5) using reiterative Grignard addition and ring-closing metathesis (RCM) as key reactions. The synthesized adenosine phosphonic acids analogues (22) and (23) were subjected to antiviral screening against HIV-1. Compound (23) exhibited moderate anti-HIV activity ($EC_50$ = 8.61 ${\mu}M$) in the CEM cell line.