Phosphororganische Verbindungen, 67. Notiz über die reduktive Umwandlung von Carbonsäuren in ihre Aldehyde

Horner, L.; Röder, Heinz

doi:10.1002/cber.19701030936

Cited by 29 publications

(2 citation statements)

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“…The isomeric phosphonate ( R )-[1- 2 H 1 ] 38 was isolated in 36% yield (ee 94%; 43% of the starting material was recovered). Here, the small amount of racemization is attributed to the retro-Abramov reaction, the decomposition of ( R )-[1- 2 H 1 ] 37 to the lithium salt of diisopropyl phosphite and [1- 2 H 1 ]formaldehyde, followed by the reverse process with the formation of both enantiomers of [1- 2 H 1 ] 37 . Racemization via metalation of ( R )-[1- 2 H 1 ] 38 is not feasible, because the amount of n -BuLi (0.9 equiv) was not even sufficient for a complete transmetalation.…”

Section: Resultsmentioning

confidence: 99%

Preparation of Chiral α-Oxy-[²H₁]methyllithiums of 99% ee and Determination of Their Configurational Stability

et al. 2007

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(Tributylstannyl)methyl 2,2,6,6-tetramethylpiperidine-1-carboxylate was metalated with t-BuLi/TMEDA at -78 degrees C and borylated with the mixed borate derived from (R,R)-1,2-dicyclohexylethane-1,2-diol and t-butanol to give diastereomeric boronates 31/32 in equal amounts. Boronates 31 and 32 were reduced with LiBEt3D and then oxidized with basic H2O2 to give (S)- and (R)-tributylstannyl-[1-2H1]methanol of 99% ee, respectively. Treatment of their respective phosphates with n-BuLi at -78 and 0 degrees C gave microscopically configurationally stable phosphinyloxy-substituted [2H1]methyllithiums, which rearranged to hydroxy-[1-2H1]methylphosphonates of ee > 98% (phosphate-phosphonate rearrangement). The N,N-diisopropylcarbamates of the enantiomeric tributylstannyl-[1-2H1]methanols were transmetalated to give carbamoyloxy-substituted chiral [2H1]methyllithiums, which were macroscopically configurationally stable for prolonged periods of time (up to 3 h, ee still 99%) at -78 degrees C, deduced from trapping experiments with benzaldehyde. The chemical stability of these methyllithiums ended at -50 degrees C. The stereochemistry of the monoprotected and monodeuterated 1-phenylethane-1,2-diols obtained was secured by spectroscopic comparison of their Mosher esters with that of all four stereoisomeric 1-phenyl-[1-2H1]ethane-1,2-diols synthesized independently. Furthermore, the configurations of the boronates and the chiral methyllithiums derived from them were deduced from a single-crystal X-ray structure analysis of a carbamate in which the tributylstannyl group had been replaced by the [(1R)-menthyl]dimethylstannyl group.

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Section: Resultsmentioning

confidence: 99%

Preparation of Chiral α-Oxy-[²H₁]methyllithiums of 99% ee and Determination of Their Configurational Stability

et al. 2007

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“…We wish to thank Mr. D. A. Kooistra for his preliminary work in this area and Dr. W. S. Mungall for his assistance in the mass spectral study. Received September 6, 1972…”

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Reaction between azide and nitronium ions. Formation and decomposition of nitryl azide

Doyle¹,

Maciejko²,

Busman³

1973

J. Am. Chem. Soc.

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Phosphorus Addition atsp²Carbon

Engel

1988

Organic Reactions

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In recent years a renewed interest in the synthesis of organophosphorus compounds has appeared. This has been the result principally of the development of new applications of materials bearing a carbon–phosphorus linkage for chemical synthesis, biological regulation, and a variety of industrial uses. In chemical syntheses the phosphoryl function has been found to be of great utility as an activator for two major categories of transformations. The first of these is the generation of new carboncarbon double bonds through the phosphoryl‐stabilized anion modifications of the Wittig reaction. For these reactions, the phosphoryl function increases the acidity of the hydrogen of the carbon attached to phosphorus and, after addition to a carbonyl linkage, is usually eliminated as a water‐soluble byproduct. Alternatively, the initially formed phosphonate anion may be used as a nucleophile in a substitution reaction leading to a derived phosphonate product having its own synthetic utility. In the second category of transformations an appropriately functionalized phosphonate reacts at the carbon attached to phosphorus to give products that can be envisioned as resulting from reaction of an electrophilic substrate with a carbonyl group of inverted polarity. The phosphoryl function, which is generally eliminated in the formation of the target material, facilitates these “umpolung” reactions that could not be accomplished directly with a parent material bearing the simple carbonoxygen double bond. With regard to biological applications, the synthesis of organophosphorus compounds has been of interest for several reasons. Among these is the discovery in a variety of organisms of naturally occurring compounds bearing the carbonphosphorus bond. Phosphonomycin and aminoethylphosphonic acid are two well‐known examples of such compounds. It has also been recognized that phosphonates may be capable of perturbing metabolic processes normally involving phosphates of similar structure. In addition, materials with other metabolic regulatory capabilities have been found. As a result, there have been not only syntheses of many new organophosphorus compounds but also the development of improved methods for such syntheses. The review presented in this chapter is concerned with one approach to carbonphosphorus bond formation that is particularly significant for the aforementioned applications, specifically the addition of a (formally) trivalent phosphorus ester or amide to an unsaturated carbon linkage under polar reaction conditions. Reactions of a variety of types of phosphorus reagents with simple carbonyl compounds, imines, and other related polar unsaturated carbon functions, as well as conjugate addition reactions, are reviewed.

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Phosphororganische Verbindungen, 67. Notiz über die reduktive Umwandlung von Carbonsäuren in ihre Aldehyde

Cited by 29 publications

References 4 publications

Preparation of Chiral α-Oxy-[²H₁]methyllithiums of 99% ee and Determination of Their Configurational Stability

Preparation of Chiral α-Oxy-[²H₁]methyllithiums of 99% ee and Determination of Their Configurational Stability

Reaction between azide and nitronium ions. Formation and decomposition of nitryl azide

Phosphorus Addition atsp²Carbon

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Phosphororganische Verbindungen, 67. Notiz über die reduktive Umwandlung von Carbonsäuren in ihre Aldehyde

Cited by 29 publications

References 4 publications

Preparation of Chiral α-Oxy-[2H1]methyllithiums of 99% ee and Determination of Their Configurational Stability

Preparation of Chiral α-Oxy-[2H1]methyllithiums of 99% ee and Determination of Their Configurational Stability

Reaction between azide and nitronium ions. Formation and decomposition of nitryl azide

Phosphorus Addition atsp2Carbon

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Preparation of Chiral α-Oxy-[²H₁]methyllithiums of 99% ee and Determination of Their Configurational Stability

Preparation of Chiral α-Oxy-[²H₁]methyllithiums of 99% ee and Determination of Their Configurational Stability

Phosphorus Addition atsp²Carbon