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Shou-Ling Huang

Publications and source records attributed to Shou-Ling Huang.

5 recordsLinked to original sources

Intramolecular metathesis of a vinyl group with vinylidene C=C double bond in Ru complexes.

The cationic complex {[Ru]=C=CHCPh2CH2CH=CH2}BF4 (3a, [Ru] = (eta5-C5H5)(PPh3)2Ru) in solution transforms to {[Ru]=C=CHCH2CPh2CH=CH2}BF4 (4a) via a new metathesis process of the terminal vinyl group with the C=C of the vinylidene group which is confirmed by 13C labeling studies. This transformation is irreversible as revealed by deuteration and decomplexation studies. The cationic complex {[Ru]=C=CHCPh2CH2CMe=CH2}BF4 (3b) undergoes a cyclization process yielding 6b containing a eta2-cyclic allene ligand which is fully characterized by single-crystal X-ray diffraction analysis. Analogous complexes 4a' and 6b' ([Ru] = (eta5-C5H5)(dppe)Ru) containing dppe ligands were similarly obtained from protonation of the corresponding acetylide complexes via formation of vinylidene intermediate. Protonation of the acetylide complex containing a terminal alkynyl group [Ru]-CCCPh2CH2CCH (2c) generates the vinylidene complex {[Ru]=C=CHCPh2CH2CCH}BF4 (3c) which again undergoes an irreversible transformation to give {[Ru]=C=CHCH2CPh2CCH}BF4 (4c) possibly via a pi-coordinated alkynyl complex followed by hydrogen and metal migration. No similar transformation is observed for the analogous dppe complex 3c'. With an extra methylene group, complex {[Ru]=C=CHCPh2CH2CH2CH=CH2}BF4 (3d) and complex {[Ru]=C=CHCPh2CH2Ph}BF4 (3e) are stable. The presence of a gem-diphenylmethylene moiety at the vinylidene ligand with the appropriate terminal vinyl or alkynyl group along with the correct steric environment implements such a novel reactivity in the ruthenium vinylidene complexes.

Journal Article↗

Furan-containing oligoaryl cyclophanene.

[structure: see text] Furan-containing oligoaryl cyclophanene 1 and the corresponding cyclophane 2 were synthesized from propargylic dithioacetal 3. The electrochemical and photophysical properties and the fluxional behavior of these molecules have been examined. The emission of 1 appeared at 499 nm whereas that of 2 appeared at 389 nm.

Journal Article↗

2,2'-Diphenyl-1-picrylhydrazyl radical-scavenging active components from adlay (Coix lachryma-jobi L. var. ma-yuen Stapf) hulls.

An activity-directed fractionation and purification process was used to identify the antioxidative components of adlay hulls. Hulls of adlay (Coix lachryma-jobi L. var. ma-yuen Stapf) were extracted with methanol and then separated into water, 1-butanol, ethyl acetate, and hexane fractions. The 1-butanol-soluble fraction exhibited greater capacity to scavenge 2,2'-diphenyl-1-picrylhydrazyl (DPPH) radicals when compared with fractions soluble in water, ethyl acetate, and hexane phases. The 1-butanol fraction was then subjected to separation and purification using Diaion HP-20 chromatography, silica gel chromatography, and HPLC. Six compounds showing strong antioxidant activity were identified by spectroscopic methods ((1)H NMR, (13)C NMR, IR, and MS) and by comparison with authentic samples to be coniferyl alcohol (1), syringic acid (2), ferulic acid (3), syringaresinol (4), 4-ketopinoresinol (5), and a new lignan, mayuenolide (6).

Antioxidants↗

Four new podocarpane-type trinorditerpenes from the bark of Taiwania cryptomerioides.

Further studies on the bark of Taiwania cryptomerioides found four new podocarpane derivatives, 1beta,13-dihydroxy-8,11,13-podocarpatriene (1), 14,18-dihydroxy-13-methoxy-8,11,13-podocarpatriene (2), 1beta,14-dihydroxy-13-methoxy-8,11,13-podocarpatriene-2,7-dione (3), and 3beta,14-dihydroxy-13-methoxy-8,11,13-podocarpatrien-7-one (4), together with a known 1beta,13,14-trihydroxy-8,11,13-podocarpatrien-7-one (5). Those structures were elucidated principally from spectral evidence.

Cupressaceae↗