Harno Dwi Pranowo
Department of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Gadjah Mada, Sekip Utara, Yogyakarta 55281

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The Acid Catalyzed Reaction of α-Pinene Over Y-Zeolite Nanik Wijayati; Harno Dwi Pranowo; Jumina Jumina; Triyono Triyono
Indonesian Journal of Chemistry Vol 13, No 1 (2013)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (2849.884 KB) | DOI: 10.22146/ijc.21327

Abstract

The hydration of α-pinene has been studied in the presence of Y-zeolite (Si/Al = 2.89) as a solid acid catalyst. The reaction was performed in batch reactor in isopropyl alcohol at various temperature and reaction time with magnetic stirrer. The acid catalyst hydration reaction of a-pinene yields a complex mixture of monoterpenes, alcohols and hydrocarbons. The selectivity of α-terpineol (the monocyclic alcohol) as main product was 59.20% with a conversion of 83.83% and the non alcoholic as the isomerization co-product as 30% after 60 min at 65 °C. The conversion and selectivity to α-terpineol increase significantly with in increase in temperature and reaction times.
THEORETICAL STUDY ON 15-CROWN-5 COMPLEX WITH SOME METAL CATIONS Yahmin Yahmin; Harno Dwi Pranowo; Ria Armunanto
Indonesian Journal of Chemistry Vol 12, No 2 (2012)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (519.918 KB) | DOI: 10.22146/ijc.21353

Abstract

The capability of 15-crown-5 ethers to form complexes with some metal cations (Li+, Na+, K+, Zn2+, Cd2+ and Hg2+) was investigated by an ab initio quantum mechanical method. The calculations were performed at the RHF/lanl2mb level of theory. The interaction energies were used to evaluate the metal binding capability of the crown ether. The effect of nature of the metal on the binding properties was also studied. The results of the calculations showed that the interaction energy of the complexes increased in proportion with the ratio of ion charge, electronegativity and ionization potential to the cation diameter. In addition, based on the extraction distribution coefficient in the gas phase, it is found that the 15-crown-5 could not extract metal cations investigated.
MACRONONE, A NOVEL DIEPOXYLIGNAN FROM BARK OF MAHKOTA DEWA (Phaleria macrocarpa (Scheff.) Boerl.) AND ITS ANTIOXIDANT ACTIVITY Susilawati Susilawati; Sabirin Matsjeh; Harno Dwi Pranowo; Chairil Anwar
Indonesian Journal of Chemistry Vol 12, No 1 (2012)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (655.052 KB) | DOI: 10.22146/ijc.21373

Abstract

Mahkota dewa (Phaleria macrocarpa (Scheff.) Boerl.) which is belong to family of Thymelaeaceae is one of Indonesian traditional medicines. Chemical constituent has been isolated from bark of mahkota dewa. Sample was extracted with methanol. Concentrated methanol extract was extracted by n-hexane, chloroform and ethyl acetate. A Compound that separated and purified by column chromatography from ethyl acetate extract is a red spherical crystal (m.p. 94-95 °C). Its spot gave yellow fluorescence at TLC plate (UV366) and has optical rotation of -9.3°(c. 2 mg/mL, methanol). Structure elucidation by UV, IR, 1H-NMR, 13C-NMR and NMR 2 dimension (HMQC, COSY, HMBC and DEPT-135) spectroscopy show that the compound gives a name macronone. Computational chemistry calculation using Hyperchem on the level of semiempirical method PM3 was confirmed the conformation of macronone. DPPH method shows that macronone has lower antioxidant activity compare to the ethyl acetate extract.
AB INITIO INVESTIGATION OF 12-CROWN-4 AND BENZO-12-CROWN-4 COMPLEXES WITH Li+, Na+, K+, Zn2+, Cd2+, AND Hg2+ Yahmin Yahmin; Harno Dwi Pranowo; Ria Armunanto
Indonesian Journal of Chemistry Vol 10, No 1 (2010)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (370.959 KB) | DOI: 10.22146/ijc.21488

Abstract

The structure and binding energies of 12-crown-4 and benzo-12-crown-4 complexes with Li+, Na+, K+, Zn2+, Cd2+, and Hg2+were investigated with ab initio calculations using Hartree-Fock approximation and second-order perturbation theory. The basis set used in this study is lanl2mb. The structure optimization of cation-crown ether complexes was evaluated at HF/lanl2mb level of theory and interaction energy of the corresponding complexes was calculated at MP2/lanl2mb level of theory (MP2/lanl2mb//HF/lanl2mb). Interactions of the crown ethers and the cations were discussed in term of the structure parameter of crown ether. The binding energies of the complexes show that all complex formed from transition metal cations is more stable than the complexes formed from alkali metal cations.