Nitrogen Mustard Derivatives Containing the Phosphonate Group<sup>1</sup>

Kagan, Fred; Birkenmeyer, Robert D.; Strube, R. E.

doi:10.1021/ja01521a029

Cited by 46 publications

(13 citation statements)

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“…For the Bu'NH, reaction the same sense of stereospecificity would obviously be expected but evidence was needed. It was obtained by treating a sample of the phosphonamidic chloride 14 having a predominance of one diastereoisomer (70% highfield 6,) with MeNH, and with Bu'NH,. In each case the predominant diastereoisomer of the product 11 or 12 formed by substitution corresponded (31P and 'H NMR spectroscopy) to the predominant diastereoisomer of the same compound formed by the rearrangement of mesylate sample A.…”

Section: Resultsmentioning

confidence: 99%

Stereospecificity in the rearrangement reactions of an N-phosphinoyl-O-sulfonylhydroxylamine with methylamine and tert-butylamine: retention of configuration at phosphorus as evidence for the initial formation of a phosphonamidic sulfonic mixed anhydride

Harger¹,

Sreedharan-Menon²

1994

J. Chem. Soc., Perkin Trans. 1

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Reaction of the N-phosphinoyl-U-sulfonylhydroxylamine PhMeCH (Ph) P(0) NHOMs 10 with RNH, ( R = Me or Bur) results in migration of the phenyl group from phosphorus to nitrogen which leads to the rearrangement product PhMeCHP(O)(NHPh)NHR. Using samples of 10 enriched in one diastereoisomer (80: 20) or the other (3: 97). the reaction with neat RNH, proceeds with a high degree of stereospecificity, thereby ruling out the possibility of a free metaphosphonimidate intermediate. For the MeNH, reaction, the relative configurations of substrate and product, deduced from their X-ray crystal structures, show the sense of the stereospecificity to be retention of configuration at phosphorus; for the Bu'NH, reaction, indirect evidence leads to the same conclusion. Retention of configuration is thought to result from initial base-induced rearrangement to the phosphonamidic sulfonic mixed anhydride PhMeCHP(0) (NHPh)OMs, with inversion of configuration at phosphorus; this then undergoes nucleophilic substitution with RN H, to give the observed product. The nucleophilic substitution can have an associative S,2( P) mechanism (inversion of configuration at phosphorus) but also a dissociative elimination-addition mechanism. The latter is responsible for departures from complete stereospecificity; these are small with MeNH, and neat Bu'NH,, but large with Bu'NH, at high dilution.N-Phosphinoylhydroxylamines such as Ph,P(O)NHOH are the phosphorus analogues of hydroxamic acids and when suitably activated they undergo a Lossen-like rearrangement with base. Thus, for example, the 0-methylsulfonyl derivative 1 (R = Ph) reacts with MeNH, or Bu'NH, to give the phosphonic diamide 3 (R' = Me or Bur) in which a phenyl group has migrated from phosphorus to nitrogen., Alkyl groups migrate much less readily than phenyl, so the unsymmetrical substrates 1 (R = alkyl) still give only the phenyl-migration products 3. Alkyl groups will migrate if there is no competing phenyl group but they do so only with r e l ~c t a n c e . ~ Rearrangement may proceed by way of a monomeric metaphosphonimidate 2 (Scheme 1 ) 1 2 3 Scheme 1 Paper 4/04207G

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Section: Resultsmentioning

confidence: 99%

Stereospecificity in the rearrangement reactions of an N-phosphinoyl-O-sulfonylhydroxylamine with methylamine and tert-butylamine: retention of configuration at phosphorus as evidence for the initial formation of a phosphonamidic sulfonic mixed anhydride

Harger¹,

Sreedharan-Menon²

1994

J. Chem. Soc., Perkin Trans. 1

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“…33, 34 The synthesis of [NC-C 6 H 4 -CH=CH-C 6 H 4 -C(H)=N(H)-B 12 H 11 ] − (3) was conducted in three steps. First, diethyl 4-cyanobenzylphosphonate was pre-pared from triethyl phosphite and 4-(bromomethyl)benzonitrile, following a procedure described by Kagan et al 35 In a second step and in the presence of potassium hydroxide, the reaction of terephthaldehyde with diethyl 4-cyanobenzylphosphonate yielded 4-cyano-4 -formylstilbene (7) (Scheme 3).…”

Section: Synthesis and Characterization Of Non-centrosymmetric P-conj...mentioning

confidence: 99%

“…The monoamino derivative [B 12 H 11 NH 3 ] − (1) was prepared from [B 12 H 12 ] 2− as described by Hertler and Raash. 2 The synthesis of [NC-C 6 H 4 -C(H)=N(H)-B 12 H 11 ] − (2) was conducted from 1 by following the procedure reported by Sivaev et al 29 The DSC analysis of 2 shows a melting point at 241 • C followed by a strong exothermic effect starting at 248 • C. In a first step, diethyl p-cyanobenzylphosphonate was synthesized according to a procedure previously reported by Kagan et al 35 In a second step, 4-cyano-4 -formylstilbene was prepared by the procedure described below, consistent with a patent deposited by Reinehr. 49 1.87g (33 mmol) of potassium hydroxide was dissolved in 25 mL of methanol at 45 • C. The solution was cooled to 0 • C, and then 4.09g (31 mmol) of terephthalaldehyde were added.…”

Section: Synthesis Of [Nc-c 6 H 4 -C(h)=n(h)-b 12 H 11 ][N(n-bu) 4 ] ...mentioning

confidence: 99%

Synthesis, characterization and optical properties of π-conjugated systems incorporating closo-dodecaborate clusters: new potential candidates for two-photon absorption processes

et al. 2005

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Non-centrosymmetric pi-conjugated systems incorporating closo-dodecaborate clusters, [NC-C6H4-C(H=N(H)-B12H11]-(2), [NC-C6H4-C(H)=C(H)-C(6)H(4)-C(H)=N(H)-B12H11]-(3), and [NC-C6H4-C(H)=C(H)-C6H4-C(H)=C(H)-C6H4-C(H)=N(H)-B12H11]-(4) have been synthesized by reaction of the monoamino derivative of B12, [B12H11NH3]-(1), with various arylaldehydes, R-C6H4-CHO. These Schiff base-like compounds were fully characterized by multinuclear NMR spectroscopy and mass spectrometry. In order to evaluate these boron rich pi-systems as potential materials for two-photon absorption (TPA) processes, UV linear absorption curves were recorded for 3 and 4, and comparatively studied with those of the boron-free pi-systems NC-C6H4-C(H)=N-CH3(5) and NC-C6H4-C(H)=C(H)-C6H4-C(H)=N-CH3(6). The donor effect of the boron cluster was evidenced by a shift to the lower energy of the absorption band in the spectra of systems incorporating B12. The two photon absorption (TPA) spectrum of compound , obtained by the up-conversion method, shows a resonance at 720 nm with a cross-section sigma(TPA) of 35 x 10(-50) cm(4) s photon(-1) molecule(-1). This value suggests the potential of B12 clusters to be used as new donor groups for the synthesis of non-linear materials.

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“…A solution of 15 25 (1.41 g, 5.60 mmol) in dry THF (10 cm 3 ) was added to a KOBu t (0.673 g, 6.00 mmol) and dry THF (10 cm 3 ). The solution was stirred for 10 min at room temperature.…”

Section: (E)-4-[2-(345-trimethoxyphenyl)vinyl]benzonitrile 17ementioning

confidence: 99%

Luminescent supramolecular assemblies based on hydrogenbonded complexes of stilbenecarboxylic acids and dithieno[3,2b:2′,3′d]thiophene2carboxylic acids with a tris(imidazoline) base

et al. 2001

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Nitrogen Mustard Derivatives Containing the Phosphonate Group¹

Cited by 46 publications

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Stereospecificity in the rearrangement reactions of an N-phosphinoyl-O-sulfonylhydroxylamine with methylamine and tert-butylamine: retention of configuration at phosphorus as evidence for the initial formation of a phosphonamidic sulfonic mixed anhydride

Stereospecificity in the rearrangement reactions of an N-phosphinoyl-O-sulfonylhydroxylamine with methylamine and tert-butylamine: retention of configuration at phosphorus as evidence for the initial formation of a phosphonamidic sulfonic mixed anhydride

Synthesis, characterization and optical properties of π-conjugated systems incorporating closo-dodecaborate clusters: new potential candidates for two-photon absorption processes

Luminescent supramolecular assemblies based on hydrogenbonded complexes of stilbenecarboxylic acids and dithieno[3,2b:2′,3′d]thiophene2carboxylic acids with a tris(imidazoline) base

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Nitrogen Mustard Derivatives Containing the Phosphonate Group1

Cited by 46 publications

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Stereospecificity in the rearrangement reactions of an N-phosphinoyl-O-sulfonylhydroxylamine with methylamine and tert-butylamine: retention of configuration at phosphorus as evidence for the initial formation of a phosphonamidic sulfonic mixed anhydride

Stereospecificity in the rearrangement reactions of an N-phosphinoyl-O-sulfonylhydroxylamine with methylamine and tert-butylamine: retention of configuration at phosphorus as evidence for the initial formation of a phosphonamidic sulfonic mixed anhydride

Synthesis, characterization and optical properties of π-conjugated systems incorporating closo-dodecaborate clusters: new potential candidates for two-photon absorption processes

Luminescent supramolecular assemblies based on hydrogen­bonded complexes of stilbenecarboxylic acids and dithieno[3,2­b:2′,3′­d]thiophene­2­carboxylic acids with a tris(imidazoline) base

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Nitrogen Mustard Derivatives Containing the Phosphonate Group¹

Luminescent supramolecular assemblies based on hydrogenbonded complexes of stilbenecarboxylic acids and dithieno[3,2b:2′,3′d]thiophene2carboxylic acids with a tris(imidazoline) base