4,5-Dihydro-3-methyl-5-(4-methylphenyl)-1H-pyrazole-1-carboxamidinium acetate acetone hemisolvate.
The X-ray structure analysis of the unexpected product of the reaction between 4-(4-methylphenyl)but-3-en-2-one and aminoguanidine revealed the title compound, C(12)H(17)N(4)(+) x -C(2)H(3)O(2)(-) x 0.5C(3)H(6)O, consisting of a protonated amidine moiety joined to a substituted pyrazoline ring at the N1 atom. The amidine group is protonated and the positive charge is delocalized over the three C[bond]N bonds in a similar manner to that found in guanidinium salts. The amidinium moiety of the cation is linked to the acetate anions through four N[bond]H...O hydrogen bonds, with N...O distances of 2.749 (4), 2.848 (4), 2.904 (4) and 2.911 (4) A. The pyrazoline ring adopts a flattened envelope conformation and the substituted phenyl ring is oriented perpendicular to the attached heterocycle. The acetone solvate molecule lies across a twofold rotation axis.
4-(3,5-Dimethyl-1H-pyrazol-4-ylmethyl)-3,5-dimethyl-1H-pyrazol-2-ium dihydrogen phosphate: a combined X-ray and DFT study.
The molecular structure of the title salt, C(11)H(17)N(4)(+).H(2)PO(4)(-), has been determined from single-crystal X-ray analysis and compared with the structure calculated by density functional theory (DFT) at the BLYP level. The crystal packing in the title compound is stabilized primarily by intermolecular N-H...O, O-H...N and O-H...O hydrogen bonds and pi-pi stacking interactions, and thus a three-dimensional supramolecular honeycomb network consisting of R(4)(2)(10), R(4)(4)(14) and R(4)(4)(24) ring motifs is established. The HOMO-LUMO energy gap (1.338 eV; HOMO is the highest occupied molecular orbital and LUMO is the lowest unoccupied molecular orbital) indicates a high chemical reactivity for the title compound.
Catalytic removal of tert-butyldimethylsilyl (TBS) ether by PVP-I
Abstract A mild, efficient and rapid protocol the deprotection of alcoholic TBDMS ethers using PVP-1 as catalyst in methanol, the procedure of deprotection of various TBDMS ethers were found to be very convenient, easy work-up, high yielding.