Biologically relevant phosphoranes: synthesis and structural characterization of glucofuranose-derived phosphoranes with penta- and hexacoordination at phosphorus.

Carbohydrate-based phosphoranes were synthesized by reacting the appropriate diphenol with phosphorus trichloride followed by the addition of chloralose to form 1 and by the addition of isopropylidene-D-glucofuranose to form 2 and 3. Phosphorane 4 was obtained by reacting 1,2-O-isopropylidene-alpha-D-glucofuranosyl-3,5,6-phosphite (13) with a diphenol. For the synthesis of 5-9, the appropriate phosphite was reacted with isopropylidene-glucofuranose.

Biologically relevant phosphoranes: structural characterization of glucofuranose- and xylofuranose-based phosphoranes.

Carbohydrate-based phosphoranes were synthesized by reacting 2,2'-ethylidenebis(4,6-di-tert-butylphenyl)fluorophosphite with 1,2-O-isopropylidene-alpha-D-glucofuranose, beta-chloralose, and 1,2-isopropylidene-alpha-D-xylofuranose to form the monocyclic biophosphoranes 1-3, respectively, in the presence of N-chlorodiisopropylamine. Synthesis of the monocyclic biophosphorane 4 was achieved by reacting tris(2,6-di-isopropylphenyl)phosphite with 1,2-O-isopropylidene-alpha-D-glucofuranose in the presence of N-chlorodiisopropylamine. X-ray analysis of 1-4 revealed trigonal bipyramidal structures with the carbohydrate components occupying axial-equatorial sites.

Biologically relevant phosphoranes: structural characterization of a nucleotidyl phosphorane.

The first successful crystal structures of biorelevant nucleoside and carbohydrate-based phosphoranes are reported. Employing thymidine, a nucleotidyl phosphorane was synthesized in 90% yield and was shown by X-ray analysis to possess a trigonal bipyramidal geometry. With the use of 1,2-O-isopropylidene-alpha-d-glucofuranose, a carbohydrate-based phosphorane was formed and similarly found to have a trigonal bipyramidal geometry.

Phosphorus-nitrogen donor interaction leading to atrane formation in phosphate and oxyphosphorane compositions. Implications for phosphoryl transfer enzymes(1).

Reaction of aminotriphenols, tris(2-hydroxy-3,5-dimethylbenzyl)amine (E) and tris(2- hydroxy-3-tert-butyl-5-methylbenzyl)amine (F), with triphenylphosphite, tris(p-methoxyphenyl)phosphite, or phenyldiphenoxyphosphane in the presence of N-chlorodiisopropylamine led to the isolation of tetraoxyphosphorane 1, pentaoxyphosphorane 3, phosphate-atrane 2, hexacoordinated pentaoxyphosphorane-atrane 4, and the first hexacoordinated tetraoxyphosphorane-atrane 5. X-ray analysis of 1-3 and 5 were obtained. NMR data is reported and supports that the atrane 4 has the same hexacoordinated structure as 5.

Influence of hydrogen bonding in competition with lattice interactions on carbonyl coordination at phosphorus. Implications for phosphoryl transfer activated states.

A series of phosphorus compounds containing carboxyl groups that serve as mimics for amino acid residues was synthesized. The series was composed of the phosphonium salts 1A, 1B, and 2, the anionic phosphines 3A and 3B, and the anionic phosphine oxide 4. X-ray structural analysis revealed that P-O coordination occurred in the presence of extensive hydrogen bonding and led to pseudo or regular trigonal bipyramidal geometries.

Pseudoheptacoordination and pseudohexacoordination in tris(2-N,N-dimethylbenzylamino)phosphane.

The phosphane (C(6)H(4)-2-CH(2)NMe(2))(3)P (1) upon recrystallization from various solvents yielded the structurally different forms 1A, 1C, 1B(1), and 1B(2). Phosphane oxide (C(6)H(4)-2-CH(2)NOMe(2))(3)PO (2) was obtained from 1 by oxidation with hydrogen peroxide. X-ray analysis provided molecular structures for 1A, 1B(1), 1B(2), and 2.

Conversion of tricoordinate to hexacoordinate phosphorus. Formation of a phosphorane-phosphatrane system.

Reaction of RPCl(2) with tris(2-hydroxy-3-tert-butyl-5-methylbenzyl)amine (4) led to the formation of a tricoordinated phosphonite (1) when R = Ph and to a hexacoordinated phosphorane-phosphatrane (2) when R = Et. The X-ray structures showed that the unreacted hydroxyl group in 1 oxidatively added to phosphorus in 2 leading to the formation of three additional bonds, a P[bond]O, a P[bond]H, and a P[bond]N linkage. In solution, (31)P measurements assisted by solid-state (31)P measurements revealed that each of the compounds existed in both structural forms.

Cyclic Three-, Four-, Five-, and Six-Coordinate Nitrogen-Containing Phosphorus Compounds Varying in Ring Size from Five- to Ten-Membered. P-N Donor Action(1).

New nitrogen-containing phosphorus compounds 1 and 3-5 were prepared by the reaction of a nitrogen-containing phenol with PhPCl(2). Hydrolysis of 1 gave an acyclic anionic phosphinate hydrogen bonded to an ammonium component (2). Use of a nitrogen-containing diol with P(OPh)(3) resulted in oxidative addition to give hexacoordinate pentaoxyphosphorus compound 6 exhibiting P-N donor action.

Molecular Structures of Three-, Four-, and Five-Coordinate Phosphorus Compounds Containing Salicylate Ligands(1).

The new cyclic compound 2,2'-sulfurylbis(4-methyl-6-tert-butylphenyl) methyl 2-benzoate phosphite, O(2)S[(t-Bu)MeC(6)H(4)O](2)(OC(6)H(4)CO(2)Me)P (3), containing a salicylate ligand was synthesized from 2,2'-sulfurylbis(4-methyl-6-tert-butylphenyl) chlorophosphite and methyl salicylate in the presence of triethylamine in ether solution. X-ray analyses of bis(methyl salicylate-O)phenylphosphine, (OC(6)H(4)CO(2)Me)(2)PPh (1), and bis(methylsalicylato-O)phenyl(tetrachlorophenylene-1,2-dioxy)phosphorane, (O(2)C(6)Cl(4))(OC(6)H(4)CO(2)Me)(2)PPh (2), as well as that for 3 were obtained. The phosphane 1 has a pseudo trigonal bipyramidal (TBP) structure due to coordination of a carbonyl oxygen atom at an axial site.

Axial Site Occupancy by the Least Electronegative Ligands in Trigonal Bipyramidal Tetraoxyphosphoranes(1).

Analogous to the formation of CH(2)[(t-Bu)(2)C(6)H(2)O](2)P(Ph)(O(2)C(6)Cl(4)) (1), the new bicyclic tetraoxyphosphoranes CH(2)[(t-Bu)(2)C(6)H(2)O](2)P(Et)(O(2)C(6)Cl(4)) (3) and CH(2)[ClC(6)H(3)O](2)P(Ph)(O(2)C(6)Cl(4)) (4) were synthesized by the oxidative addition of the appropriate cyclic phosphines with o-tetrachlorobenzoquinone. For the formation of CH(2)[(t-Bu)(2)C(6)H(2)O](2)P(Ph)(O(2)C(2)Ph(2)) (2), a similar reaction was followed with the use of benzil (PhCOCOPh) in place of o-tetrachlorobenzoquinone. X-ray analysis of 1-3 revealed trigonal bipyramidal geometries and provided evidence for the first series of complexes in the absence of ring strain in which the least electronegative group, ethyl or phenyl, is located in an axial position, in violation of the electronegativity rule.