Photorearrangements of benzyl phosphites. Stereochemistry at phosphorus

Cairns, Shayne; Bentrude, Wesley G.

doi:10.1016/s0040-4039(01)80349-x

Cited by 17 publications

(15 citation statements)

References 12 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…A solution of 9-anthrylmethyl dimethyl phosphite (2) in deoxygenated benzene (ca. 0.03 M) was prepared under an argon atmosphere.…”

Section: Procedures For the Solution Photochemistry Of Phosphitementioning

confidence: 99%

“…Phosphite (2) The reaction of dimethyl diethylphosphoramidite (2.6 g, 16 mmol) and 9-anthrylmethanol (2.9 g, 14 mmol), followed by flash chromatography (90:5:5 diethyl ether:ethyl acetate:triethylamine), gave 2 as a yellow, thick oil (1.3 g, 4.2 mmol, 30%). …”

Section: Preparation Of 9-anthrylmethyl) Dimethylmentioning

confidence: 99%

“…It has been discovered in our research group that benzyl phosphites readily undergo photochemical Arbuzov rearrangement to benzylphosphonates upon irradiation with UV light [1,2]. The application of this rearrangement to the synthesis of acyclic nucleoside-based phosphonates has been demonstrated [3,4].…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

The photo-Arbuzov rearrangement of dimethyl 9-anthrylmethyl phosphite and the photodimerization of the corresponding phosphonate

et al. 1998

Self Cite

View full text Add to dashboard Cite

“…A solution of 9-anthrylmethyl dimethyl phosphite (2) in deoxygenated benzene (ca. 0.03 M) was prepared under an argon atmosphere.…”

Section: Procedures For the Solution Photochemistry Of Phosphitementioning

confidence: 99%

Section: Preparation Of 9-anthrylmethyl) Dimethylmentioning

confidence: 99%

See 1 more Smart Citation

The photo-Arbuzov rearrangement of dimethyl 9-anthrylmethyl phosphite and the photodimerization of the corresponding phosphonate

et al. 1998

Self Cite

View full text Add to dashboard Cite

“…This laboratory has reported studies of the facile photoinduced Arbuzov rearrangements of dialkyl benzyl phosphites, e.g., 1 → 2 , − and the useful application of this new photoreaction to the synthesis of acyclic nucleoside-based phosphonates. , The quantum yield for formation of phosphonate 2 , Φ P , at 266 nm is 0.43 . At 75% phosphite conversion, the accountability yield of 2 , based on 1 consumed, is 67% and is accompanied by a 3% accountability yield of bibenzyl, PhCH 2 CH 2 Ph .…”

Section: Introductionmentioning

confidence: 99%

“…However, it is clear that were the benzylic carbon of the radical pair 3 or 6 a stereogenic center, loss of stereochemistry at that carbon center would accompany the photorearrangement were it to proceed via a radical pair of sufficient lifetime. Because the chemical yields of phosphonates in photo-Arbuzov reactions are reasonably good, − the stereochemistry in question is of interest from a synthetic, as well as mechanistic, standpoint. This process, if stereoselective, potentially provides an attractive way to introduce, in stereoselective fashion, a stereogenic carbon center of known configuration attached directly to phosphorus.…”

Section: Introductionmentioning

confidence: 99%

Photo-Arbuzov Rearrangements of Benzylic Phosphites. Stereochemistry at Migratory Carbon

1998

Self Cite

View full text Add to dashboard Cite

The stereochemistry of the photo-Arbuzov rearrangement of the benzylic phosphite trans-(R,R‘)-10 to the corresponding phosphonate, 11, has been determined by 31P NMR spectroscopy and X-ray crystallography. The reaction is shown to occur with predominant retention of configuration at the stereogenic migratory carbon center of configuration R‘ in starting trans-(R,R‘)-10 and the predominant product cis-(R,R‘)-11. Thus, reaction of optically active phosphoramidite 13 (R/S ratio 98/2, 96% ee) with 1-phenylethanol of high optical purity (R‘/S‘ ratio, 97/3, 94% ee) gives phosphite trans-10 (cis/trans ratio ≥ 97/3) almost entirely as the single enantiomer, trans-(R,R‘)-10. Irradiation of trans-(R,R‘)-10 in acetonitrile with 254 nm ultraviolet light converted it cleanly to two diastereomers of phosphonate cis- 11 in 80/20 ratio (31P NMR). The major (80%) isomer was isolated, recrystallized, and shown by X-ray crystallography to be cis-(R,R‘)-11. The lesser (20%) product is identified, on the basis of its 31P NMR chemical shift, as the diastereomer cis-(R,S‘)-11. (Assignments derived from photorearrangement of totally racemic cis-10 prepared from reaction of racemic 1-phenylethanol with racemic 13.) The generation of trans-(R,S‘)-11 is attributed to the formation (Scheme ) from trans-(R,R‘)-10 of short-lived, predominantly singlet, free radical pairs (12a) that largely (≃80%) undergo combination to form cis-(R,R‘)-11. To a lesser extent (≃20%), the 1-phenylethyl radicals (C) of the pair 12a are converted by rotation to C‘ to generate the stereochemically distinct radical pair 12b that then combines to form cis-(R,S‘)-11. To a first approximation, combination (k comb ) is four times as fast as rotation (k rot ). During the photorearrangement the trans/cis ratios of starting phosphite 10 and product phosphonate 11 are unchanged as is consistent with the generation of phosphinoyl radical B that is configurationally stable at phosphorus.

show abstract

The Synthesis of Phosphonic and Phosphinic Acids and their Derivatives: Non‐Functionalized Acids

Edmundson¹

2009

Patai's Chemistry of Functional Groups

View full text Add to dashboard Cite

Introduction The Formation of P  C ( sp 3 ) Bonds. Syntheses of Alkyl, Cycloalkyl and Aralkyl Phosphonic and Phosphinic Acids The Formation of P  C ( sp 2 ) Bonds. Syntheses of Alkenyl and Alkadienyl Phosphonic and Phosphinic Acids The Formation of P  C ( sp ) Bonds. Syntheses of Alkynyl Phosphonic and Phosphinic Acids The Formation of P  C (Aromatic) Bonds. Syntheses of Aryl Phosphonic and Phosphinic Acids Syntheses of Phosphonic and Phosphinic Acids by Modification Procedures

show abstract

Photorearrangements of benzyl phosphites. Stereochemistry at phosphorus

Cited by 17 publications

References 12 publications

The photo-Arbuzov rearrangement of dimethyl 9-anthrylmethyl phosphite and the photodimerization of the corresponding phosphonate

The photo-Arbuzov rearrangement of dimethyl 9-anthrylmethyl phosphite and the photodimerization of the corresponding phosphonate

Photo-Arbuzov Rearrangements of Benzylic Phosphites. Stereochemistry at Migratory Carbon

The Synthesis of Phosphonic and Phosphinic Acids and their Derivatives: Non‐Functionalized Acids

Contact Info

Product

Resources

About