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Hexa-acetate-tetra-aqua-trimanganese diglycine dihydrated retains the two-dimensional character of commercial manganese diacetate tetrahydrate. The manganese atoms assemble in short centrosymetric chains that are further bridged through the carboxylic group of the acetate ions agglomerating the chains into a two-dimensional pattern. The layers are bonded through H-bonds involving the zwitterionic glycine and the solvate water molecules. Susceptibility measurements show a ferrimagnetic behaviour of the sample.

Intramolecular dipolar cycloaddition of bicyclic münchnones, 5H,7H-thiazolo[3,4-c]oxazol-4-ium-1-olates, derived from cyclodehydration of 2-substituted-N-acylthiazolidine-4-carboxylic acids are reported. A range of new pyrrolo[1,2-c]thiazole derivatives (7, 14, 15, 20, 23, and 26) were obtained as single enantiomers from 2-phenylthiazolidines, 2-benzoylthiazolidines, and 2-methylthiazolidine-4-carboxylates. Pyrrolo[1,2-c][1,4]thiazine derivative 27 was also obtained from pyrrolo[1,2-c]thiazole derivative 26. The structures of methyl (2R,4R)-2-(p-methoxybenzoyl)thiazolidine-4-carboxylate (17a), methyl (2R,4R)-2-(p-methoxybenzoyl)-N-(prop-2-ynyloxyacetyl)thiazolidine- 4-carboxylate (18), and 3-oxo-4-phenyl-3,4,6,8-tetrahydro-1H-furo[3',4':2,3]pyrrolo[1,2-c][1,4]thiazine (27) were determined by X-ray crystallography. Chirooptical studies of the pyrrolo[1,2-c]thiazoles were done by confirming the absolute configuration at the chiral center C-3.

(2R,4R)-N-Acyl-2-phenylthiazolidine-4-carboxylic acids were used to generate 5H,7H-thiazolo[3,4-c]oxazol-4-ium-1-olates with internal dipolarophiles. The intramolecular 1,3-dipolar cycloaddition of these mesoionic species led to the synthesis of new 1H-pyrrolo[1,2-c]thiazole derivatives (8a, 8b and 12) as single enantiomers. The structure of 8a was determined by X-ray crystallography.

(5R)-3-Methyl-5-phenyl-5H,7H-thiazolo[3,4-c]oxazol-4-ium-1-olate was generated in the presence of a range of dipolarophiles. The intermolecular 1,3-dipolar cycloaddition of this mesoionic species led to the synthesis of chiral 1H-pyrrolo[1,2-c]thiazole derivatives 7a, 7b, 8, 14, 18, 19 and 20. In the reaction with methyl and ethyl vinyl ketone, spiro compounds 9 and 15 were also obtained. The structure of compound 15 was determined by X-ray crystallography.

Intermolecular 1,3-dipolar cycloaddition of (5R)- and (5S)-3,5-diphenyl-5H,7H-thiazolo[3,4-c]oxazol-4-ium-1-olates, (5R)- and (5S)-3-(p-methoxyphenyl)-5-phenyl-5H,7H-thiazolo-[3,4-c]oxazol-4-ium-1-olates with a range of dipolarophiles is described. New chiral 5-aryl-3-phenyl-1H,3H-pyrrolo[1,2-c]thiazoles with R and S configuration were obtained. The structure of methyl (3R)-3-phenyl-5-(p-methoxyphenyl)-1H,3H-pyrrolo[1,2-c]thiazole-6-carboxylate was determined by X-ray crystallography. The synthesis of 7,7a-dihydro-1H,3H-pyrrolo[1,2-c]thiazole-6,7-dicarboxylates was also achieved.

Nucleophilic substitution reactions of 2-halo-2H-azirines 1a, 1b, 1d, and 1e with potassium phthalimide and aniline allowed the preparation of new substituted 2H-azirines 2-5. The reactions of 2-bromo-2H-azirine 1a with methylamine led to the synthesis of alpha-diimines 7 and 8. 2-Halo-2H-azirines were also established as building blocks for the synthesis of a range of heterocyclic compounds, namely, quinoxalines 10a-10d, 3-oxazoline 14, and 2H-[1,4]oxazines 18 and 20. X-ray crystal structures of alpha-diimine 7, 3-oxazoline 14, and 2H-[1,4]oxazine 18 are reported.

Intermolecular 1,3-dipolar cycloaddition of (5R)- and (5S)-3,5-diphenyl-5H,7H-thiazolo[3,4-c]oxazol-4-ium-1-olates, (5R)- and (5S)-3-(p-methoxyphenyl)-5-phenyl-5H,7H-thiazolo-[3,4-c]oxazol-4-ium-1-olates with a range of dipolarophiles is described. New chiral 5-aryl-3-phenyl-1H,3H-pyrrolo[1,2-c]thiazoles with R and S configuration were obtained. The structure of methyl (3R)-3-phenyl-5-(p-methoxyphenyl)-1H,3H-pyrrolo[1,2-c]thiazole-6-carboxylate was determined by X-ray crystallography. The synthesis of 7,7a-dihydro-1H,3H-pyrrolo[1,2-c]thiazole-6,7-dicarboxylates was also achieved. http://www.sciencedirect.com/science/article/B6THR-45TJTNH-4/1/51920ff46ddfc9dacd686de4d95b0dae

The title compound, C3H7NO2*C3H8NO2+*NO3-, contains L-alanine-alaninium dimers bonded via the carboxyl groups by a strong asymmetric hydrogen bond with an O...O distance of 2.4547 (19) A. The neutral alanine molecule exists as a zwitterion, where the carboxyl group is dissociated and the amino group is protonated. The alaninium cation has both groups in their acidic form. The alanine molecule and the alaninium cation differ only slightly in their conformation, having an N-C(alpha)-C=O torsion angle close to -25 degrees. The dimers and the nitrate anion are joined through a three-dimensional hydrogen-bond network, in which the full hydrogen-bonding capabilities of the amino groups of the two alanine moieties are realised.

The N-aryl pyrrolidine diphosphine (R,R)-N-phenyl-3,4-bis(diphenylphosphino)pyrrolidine was obtained from natural tartaric acid. Contrary to our preliminary expectations, this new chiral ligand proved to be less selective than the corresponding N-benzyl pyrrolidine diphosphine. An attempted explanation of the observed behaviour based on the stereochemistry of the ligand as shown by X-ray crystallography is presented. http://www.sciencedirect.com/science/article/B6TGM-42G6XGY-8/1/25fa9c4e0f48edebc992db1e0b302bf0

The crystal structure of C13H14N3+FHF− is reported. The structure contains the strong hydrogen-bonded system, the bifluoride anion FH···F−. The geometry of this anion deviates significantly from linearity but has the H atom in an approximate centered position. The F···F distance is 2.293(3) A, considerably less than twice the van der Waals radius of fluorine, as expected from a very strong hydrogen bond. One of the phenyl rings of the diphenylguanidinium counter ion of the bifluoride anion is oriented syn to the unsubstituted N atom of the guanidine group, the other adopts an anti conformation. The anions and cations are held together by a layered two-dimensional network of hydrogen bonds. Both NH and NH2 groups of the cation are donors towards the fluoride ions, exhausting the potential of diphenylguanidine for hydrogen bonding.

The crystal structure of 3C13H14N3+FeF63-·3.5H2O was determined. Both phenyl rings of the diphenylguanidine cation are oriented syn to the central C=NH2 group. The anions and cations are held together by a three-dimensional network of hydrogen bonds. In the synthesis of this compound, a second phase (iron trifluoride trihydrate) was formed and identified by powder diffraction data. Mössbauer results show two different iron environments compatible with the two phases reported. http://www.sciencedirect.com/science/article/B6TGD-41C2VKP-B/1/b01b2e4d69d47aa816d3c649782ba41c

(5R)-3-Methyl-5-phenyl-5H,7H-thiazolo[3,4-c]oxazol-4-ium-1-olate was generated in the presence of a range of dipolarophiles. The intermolecular 1,3-dipolar cycloaddition of this mesoionic species led to the synthesis of chiral 1H-pyrrolo[1,2-c]thiazole derivatives 7a, 7b, 8, 14, 18, 19 and 20. In the reaction with methyl and ethyl vinyl ketone, spiro compounds 9 and 15 were also obtained. The structure of compound 15 was determined by X-ray crystallography. http://www.sciencedirect.com/science/article/B6THR-407GGNF-K/1/23c3db756f6ed9f6caefffc1d46ba51a

In previous papers, we reported that thiazolidines derived from cysteine methyl ester and aldehydes react with silver carbonate and DBU; the reactions produce transient 1-substituted methyl 2-azadiene-3-carboxylates that act as dienes in the Diels-Alder reaction.1 When we apply the same procedure to the thiazolidines 1a-d we find that the products are isolable cross-conjugated bis(enamines) 3a-d, the more stable tautomers of the azadienes 2a-d (Scheme 1). This is a new versatile route to enamines of this type. The diester 3a is a known compound that has previously been prepared from methyl â-halo-R-aminopropionate hydrohalides by reaction with bases;2 compounds 3b-d are previously unknown. Other cross-conjugated bis(enamines) of this type have been produced by thermal rearrangement of vinylaziridines.3 These compounds undergo an interesting photocyclization to 3,4-dihydropyrroles that can be intercepted, as 1,3-dipoles, in cycloaddition reactions with alkenes and alkynes.2b,3,4 Compound 3a is also reported to react as an electrophile with hydrazines5 and with primary amines,6 giving hydrazones and imines of methyl pyruvate as products. In an attempt to cyclize the diester 3a directly to dimethyl pyrrole-2,5-dicarboxylate by using DDQ as an oxidant, a single product was isolated in high yield. Instead of the pyrrole, it proved to be an interesting 1:1 adduct of the diester and DDQ whose structure 4 was established for the compound by X-ray crystallography (Figure 1). The X-ray analysis clearly shows that the C9-C10N1-C2-C3-C4 and C4-C5-C6-C7-C8-C9 rings are fused cis around the common C4-C9 bond and are furthermore linked by the methylenic bridge C10-C11C5. The conformation of the two above-mentioned rings is intermediate between E1 envelope and H2 half-chair, as shown by the ring puckering parameters7 Q ) 0.662(4) A, θ ) 53.8(3)°, φ ) 13.9(4)° [C9-C10-N1-C2-C3C4], Q ) 0.630(4) A, θ ) 53.8(4)°, φ ) 8.2(5)° [C4-C5C6-C7-C8-C9]. The conformation of the bridging ring C4-C5-C11-C10-C9 is very close to T1 (twisted around the C4-C9 bond), as shown by the puckering parameters Q(2) ) 0.566(4) A, φ(2) ) 163.3(4)°. The H1 atom is shared in a bifurcated intramolecular hydrogen bond [N1-H1‚‚‚O1: 2.714(4) A; N1-H1‚‚‚O4: 2.677(5) A, sum of the valence angles around H1 ) 358.2°]. The methoxycarbonyl group attached to the sp2 C2 atom is almost coplanar with the plane defined by the C10-N1-C2 atoms, whereas the other methoxycarbonyl group that is attached to the tetrahedric C10 atom is twisted by -16.9(5)° around the C10-C12 single bond. The H5 atom of the hydroxyl group is also involved in a bifurcated † Departamento de Quimica. ‡ Departamento de Fisica. (1) (a) Gilchrist, T. L.; Rocha Gonsalves, A. M. d’A.; Pinho e Melo, T. M. V. D. Tetrahedron 1994, 50, 13709-13724. (b) Pinho e Melo, T. M. V. D.; Fausto, R.; Rocha Gonsalves, A. M. d’A.; Gilchrist, T. L. J. Org. Chem. 1998, 63, 5350-5355. (2) (a) Mitsuhashi, K. Asahi Garasu Kogyo Gijutsu Shoreikai Kenkyu Hokoku 1973, 23, 355-362; Chem. Abstr. 1975, 82, 86591. (b) Zaima, T.; Matsunaga, Y.; Mitsuhashi, K. J. Heterocycl. Chem. 1983, 20, 1-4. (3) Gelas-Mialhe, Y.; Mabiala, G.; Vessiere, R. J. Org. Chem. 1987, 52, 5395-5400. (4) (a) Zaima, T.; Matsuno, C.; Matsunaga, Y.; Mitsuhashi, K. J. Heterocycl. Chem. 1984, 21, 445-448. (b) Zaima, T.; Matsuno, C.; Matsunaga, Y.; Mitsuhashi, K. Nippon Kagaku Kaishi 1984, 12931298; Chem. Abstr. 1984, 101, 230340. (5) Zaima, T.; Mitsuhashi, K. Nippon Kagaku Kaishi 1979, 901905; Chem. Abstr. 1979, 91, 140303. (6) Zaima, T.; Matsuno, C.; Mitsuhashi, K. Nippon Kagaku Kaishi 1983, 152-156; Chem. Abstr. 1983, 98, 179141. (7) Cremer, D.; Pople, J. A. J. Am. Chem. Soc. 1975, 97, 1354. Figure 1. X-ray structure of compound 4.

(2R,4R)-N-Acyl-2-phenylthiazolidine-4-carboxylic acids were used to generate 5H,7H-thiazolo[3,4-c]oxazol-4-ium-1-olates with internal dipolarophiles. The intramolecular 1,3-dipolar cycloaddition of these mesoionic species led to the synthesis of new 1H-pyrrolo[1,2-c]thiazole derivatives (8a, 8b and 12) as single enantiomers. The structure of 8a was determined by X-ray crystallography.