ASEAN Synergy to Overcome Challenges in Investment Arbitration

Cambodia, Indonesia, Lao, Malaysia, Thailand, and the Philippines, have been sued by foreign investors through International investment arbitrations (IIA). No matter whether the outcome is favorable or not, those countries have spend significant time, energy, and financial resources to arbitrate. ASEAN countries are not in advantageous position in IIA.The first and the most obvious reason is language barrier. Arbitration proceedins are mainly conducted in English. Consequently, the arbitrators and counsels more often than not come from English speaking countries. Not only do they lead to high cost, but also they lack of familiarity with South East Asia\u27s social, politics, economic, culture and customs. This may influence how they treat the cases such as the interpretation of provisions specifically designed to protect foreign investors such as: national treatment; fair and equitable treatment; most favored nation; and also in deciding jurisdictional issues. regional news as a legal basis for foreign investment activities aim to provide protection for foreign investor. On the other hand, it also serves as a mean to facilitate economic development in the host states of investment. Unfortunately, BITs often contain excessive and limitless protection clauses in order to attract foreign investors. This may endanger host states position as it can be used as a weapon by the investors to sue the host states. In responding to this fact, it is necessary to strengthen cooperation among ASEAN members in dealing with foreign investors through BIT. The ideal picture will be that SEA is pro-market and pro-arbitration reform. It is unavoidable that in order to protect themselves from harsh investors as well as intricate arbitration, ASEAN would be better off having its own investment arbitration center run by its experts. Thus, the short-term challenge is to equip legal practitioners, business players and academicians with more knowledge, skills and experiences in dealing with investment disputes. The long-term step will be to negotiate model of investment treaties applicable in the region and to harmonize national investment laws. These efforts are strategic opportunities for ASEAN as single market to keep balance between promoting investment, protecting investors and the host states at the same time

Recurrence of Carboxylic Acid−Pyridine Supramolecular Synthon in the Crystal Structures of Some Pyrazinecarboxylic Acids

X-ray crystal structures of pyrazinic acid 1 and isomeric methylpyrazine carboxylic acids 2−4 are analyzed to examine the occurrence of carboxylic acid−pyridine supramolecular synthon V in these heterocyclic acids. Synthon V, assembled by (carboxyl)O−H···N(pyridine) and (pyridine)C−H···O(carbonyl) hydrogen bonds, controls self-assembly in the crystal structures of pyridine and pyrazine monocarboxylic acids. The recurrence of acid−pyridine heterodimer V compared to the more common acid−acid homodimer I in the crystal structures of pyridine and pyrazine monocarboxylic acids is explained by energy computations in the RHF 6-31G* basis set. Both the O−H···N and the C−H···O hydrogen bonds in synthon V result from activated acidic donor and basic acceptor atoms in 1−4. Pyrazine 2,3- and 2,5-dicarboxylic acids 10 and 11 crystallize as dihydrates with a (carboxyl)O−H···O(water) hydrogen bond in synthon VII, a recurring pattern in the diacid structures. In summary, the carboxylic acid group forms an O−H···N hydrogen bond in pyrazine monocarboxylic acids and an O−H···O hydrogen bond in pyrazine dicarboxylic acids. This structural analysis correlates molecular features with supramolecular synthons in pyridine and pyrazine carboxylic acids for future crystal engineering strategies

Molecular Complexes of Homologous Alkanedicarboxylic Acids with Isonicotinamide: X-ray Crystal Structures, Hydrogen Bond Synthons, and Melting Point Alternation

Crystallization of α,ω-alkanedicarboxylic acids (HOOC−(CH2)n-2−COOH, n = 2−6) with isonicotinamide (IN) is carried out in 1:2 and 1:1 stoichiometry. Five cocrystals of (diacid)·(IN)2 composition (diacid = oxalic acid, malonic acid, succinic acid, glutaric acid, and adipic acid) are characterized by X-ray diffraction at 153(2) K. Tapes of acid−pyridine O−H···N and amide−amide N−H···O hydrogen bond synthons stabilize these five crystal structures as predicted by the hierarchic model:  the best donor (COOH) and best acceptor group (pyridine N) hydrogen bond as acid−pyridine and the second best donor−acceptor group (CONH2) aggregates as an amide dimer. Glutaric acid and adipic acid cocrystallize in 1:1 stoichiometry also, (diacid)·(IN), with acid−pyridine and acid−amide hydrogen bonds. Synthon energy calculations (ΔEsynthon, RHF/6-31G**) explain the observed hydrogen bond preferences in 1:2 (five examples) and 1:1 (two examples) cocrystals. The acid−pyridine hydrogen bond is favored over the acid−amide dimer for strong carboxylic acids because the difference between ΔEacid-pyridine and ΔEacid-amide (−2.21 kcal mol-1) is greater than the difference for weak acids (−0.77 kcal mol-1), which cocrystallize with both of these hydrogen bond synthons. We suggest ΔEsynthon as a semiquantitative parameter to rank hydrogen bond preferences and better understand supramolecular organization in the multifunctional acid−IN system. Melting point alternation in five homologous (diacid)·(IN)2 cocrystals is correlated with changes in crystal density and packing fraction

Molecular Complexes of Homologous Alkanedicarboxylic Acids with Isonicotinamide: X-ray Crystal Structures, Hydrogen Bond Synthons, and Melting Point Alternation

Crystallization of α,ω-alkanedicarboxylic acids (HOOC−(CH2)n-2−COOH, n = 2−6) with isonicotinamide (IN) is carried out in 1:2 and 1:1 stoichiometry. Five cocrystals of (diacid)·(IN)2 composition (diacid = oxalic acid, malonic acid, succinic acid, glutaric acid, and adipic acid) are characterized by X-ray diffraction at 153(2) K. Tapes of acid−pyridine O−H···N and amide−amide N−H···O hydrogen bond synthons stabilize these five crystal structures as predicted by the hierarchic model:  the best donor (COOH) and best acceptor group (pyridine N) hydrogen bond as acid−pyridine and the second best donor−acceptor group (CONH2) aggregates as an amide dimer. Glutaric acid and adipic acid cocrystallize in 1:1 stoichiometry also, (diacid)·(IN), with acid−pyridine and acid−amide hydrogen bonds. Synthon energy calculations (ΔEsynthon, RHF/6-31G**) explain the observed hydrogen bond preferences in 1:2 (five examples) and 1:1 (two examples) cocrystals. The acid−pyridine hydrogen bond is favored over the acid−amide dimer for strong carboxylic acids because the difference between ΔEacid-pyridine and ΔEacid-amide (−2.21 kcal mol-1) is greater than the difference for weak acids (−0.77 kcal mol-1), which cocrystallize with both of these hydrogen bond synthons. We suggest ΔEsynthon as a semiquantitative parameter to rank hydrogen bond preferences and better understand supramolecular organization in the multifunctional acid−IN system. Melting point alternation in five homologous (diacid)·(IN)2 cocrystals is correlated with changes in crystal density and packing fraction

Phenyl-Perfluorophenyl Synthon Mediated Cocrystallization of Carboxylic Acids and Amides

The significance of face-to-face π−π stacking of phenyl and perfluorophenyl rings (Ph-PhF), a robust supramolecular synthon in aromatic and perfluoroaromatic crystal structures, is studied in the cocrystallization of simple aromatic carboxylic acids and amides. X-ray crystal structures of C6H5COOH·C6F5COOH 1, C6H5CONH2·C6F5CONH2 2, and C6H5CONH2·C6F5COOH 3 are analyzed to understand the role of Ph-PhF synthon in directing self-assembly and hydrogen bonding in these cocrystals. The strong hydrogen bond donor acidity of C6F5COOH and C6F5CONH2 together with mixed stacks of phenyl and perfluorophenyl rings steer acid···acid and amide···amide hydrogen bonding in cocrystals 1 and 2. Acid···amide hydrogen bonding is sufficiently strengthened by donor acidity and acceptor basicity in 3 that the role of the Ph-PhF synthon is weaker because the aromatic rings stack with lateral offset. The complex C6H5COOH·C6F5CONH2 4 could not be obtained under similar crystallization conditions. The crystal structure of C6F5CONH2 is determined to compare molecular conformation and hydrogen bonding with motifs in the cocrystals. This study shows the viability of the Ph-PhF synthon in the presence of strong hydrogen bonding COOH and CONH2 groups for crystal engineering

N-Heterocyclic Carbene−Transition Metal Complexes: Spectroscopic and Crystallographic Analyses of π-Back-bonding Interactions

The ability of N-heterocyclic carbenes (NHCs) to participate in π-back-bonding interactions was evaluated in a range of transition metal complexes. Rh chloride complexes containing a systematic series of various 1,3-dimethyl-4,5-disubstituted-imidazol-2-ylidenes and either 1,5-cyclooctadiene (cod) or two carbon monoxide ligands were synthesized (i.e., (NHC)RhCl(cod) and (NHC)RhCl(CO)2, respectively) and studied using 1H NMR and IR spectroscopies. In the former series, the 1H NMR chemical shifts of the signals attributable to the olefin trans to the NHC ligand were found to shift downfield by up to 0.17 ppm as the π-acidity of the substituents on the 4,5-positions increased (i.e., H → Cl → CN). Similarly, in the latter series, the IR stretching frequencies of the carbonyl groups trans to the NHC ligands were found to increase by 11 ± 0.5 cm-1 as π-acidity increased over the same series. Using the nitrile group as a diagnostic handle, the CN stretching frequency of (1,3-dimethyl-4,5-dicyanoimidazol-2-ylidene)(cod)RhCl was found to be 4 ± 0.5 cm-1 higher than 1,3-dimethyl-4,5-dicyanoimidazol-2-ylidene)(CO)2RhCl, a more π-acidic analogue. X-ray analysis of the aforementioned series of (NHC)(cod)RhCl complexes indicated changes in N−Ccarbene bond lengths that were consistent with greater π-donation from complexes containing 4,5-dihydroimidazol-2-ylidene relative to the their 4,5-dicyano analogues. Collectively, these results suggest not only that imidazol-2-ylidenes are capable of π-back-bonding but that this interaction may be tuned by changing the π-acidity of the substituents on the imidazole ring

Positive Homotropic Allosteric Binding of Silver(I) Cations in a Schiff Base Oligopyrrolic Macrocycle

The binuclear silver(I) complex of a Schiff base oligopyrrolic macrocycle was prepared in high yield and fully characterized. UV−visible absorption and 1H NMR spectroscopic analyses reveal that coordination of Ag(I) cations is subject to a strong positive homotropic allosteric effect

Calix[4]pyrrole[2]carbazole: A New Kind of Expanded Calixpyrrole

The synthesis and anion binding properties of a new class of calixpyrrole analogue, containing two carbazole subunits in lieu of two of the four acetone bridging elements normally found in calix[4]pyrrole, is described. The compound exists in a winglike structure in the solid state, as judged from single-crystal X-ray diffraction analyses of both the free system and the corresponding benzoate anion complex. Evidence for anion binding in dichloromethane solution was obtained from static fluorescent quenching experiments; these latter revealed a slight preference for acetate relative to other carboxylate anions (e.g., benzoate, oxalate, succinate), as well as various other anionic substrates (i.e., chloride and dihydrogen phosphate). No evidence of binding was observed in the case of bromide, nitrate, and hydrogen sulfate

Arrested Catalysis: Controlling Kumada Coupling Activity via a Redox-Active N-Heterocyclic Carbene

Optimized syntheses for 1,3-dimesitylnaphthoquinimidazolium chloride [1H][Cl] and the corresponding silver−NHC complex [AgCl(1)] (2) were developed, enabling access to this versatile reagent in near-quantitative yield. Transmetalation from 2 to [NiCl2(PPh3)2], trans-[PdCl2(PhCN)2], or trans-[PtCl2(PhCN)2] afforded the Group 10 complexes trans-[MCl2(1)2] (3a−c, M = Ni, Pd, and Pt, respectively) in excellent overall yield (>95%) after three steps from commercially available starting materials. Electrochemical measurements indicated that the E1/2 and ΔE1/2 values for the quinone reduction couples were independent of the identity of the bridging transition metal in these complexes. Whereas attempts to isolate the reduced complexes were unsuccessful, UV/vis spectroelectrochemical analysis confirmed that electrochemical reduction of 3a−c in situ afforded optical difference spectra consistent with the formation of the expected reduced species. Complex 3a was found to catalyze the Kumada cross-coupling reaction between PhMgCl and a range of bromoarenes at room temperature. Addition of 2 equiv of cobaltocene (with respect to 3a) to the coupling reaction with bromotoluene caused a decrease in catalytic activity (from 4.7 × 10−5 to 2.7 × 10−6 s−1), which was attributed to the conversion of 3a to an arrested state. Subsequent introduction of ferrocenium tetrafluoroborate (2 equiv with respect to 3a) restored a significant degree of catalytic activity (kobs = 1.2 × 10−5 s−1). Redox-switching experiments performed over different time scales revealed that the catalyst was stable in the reduced/inactive state and that extended durations in this state did not impede catalytic reactivation upon subsequent oxidation

N-Heterocyclic Carbene−Transition Metal Complexes: Spectroscopic and Crystallographic Analyses of π-Back-bonding Interactions

The ability of N-heterocyclic carbenes (NHCs) to participate in π-back-bonding interactions was evaluated in a range of transition metal complexes. Rh chloride complexes containing a systematic series of various 1,3-dimethyl-4,5-disubstituted-imidazol-2-ylidenes and either 1,5-cyclooctadiene (cod) or two carbon monoxide ligands were synthesized (i.e., (NHC)RhCl(cod) and (NHC)RhCl(CO)2, respectively) and studied using 1H NMR and IR spectroscopies. In the former series, the 1H NMR chemical shifts of the signals attributable to the olefin trans to the NHC ligand were found to shift downfield by up to 0.17 ppm as the π-acidity of the substituents on the 4,5-positions increased (i.e., H → Cl → CN). Similarly, in the latter series, the IR stretching frequencies of the carbonyl groups trans to the NHC ligands were found to increase by 11 ± 0.5 cm-1 as π-acidity increased over the same series. Using the nitrile group as a diagnostic handle, the CN stretching frequency of (1,3-dimethyl-4,5-dicyanoimidazol-2-ylidene)(cod)RhCl was found to be 4 ± 0.5 cm-1 higher than 1,3-dimethyl-4,5-dicyanoimidazol-2-ylidene)(CO)2RhCl, a more π-acidic analogue. X-ray analysis of the aforementioned series of (NHC)(cod)RhCl complexes indicated changes in N−Ccarbene bond lengths that were consistent with greater π-donation from complexes containing 4,5-dihydroimidazol-2-ylidene relative to the their 4,5-dicyano analogues. Collectively, these results suggest not only that imidazol-2-ylidenes are capable of π-back-bonding but that this interaction may be tuned by changing the π-acidity of the substituents on the imidazole ring