Synthesis of cyanohydrins from cyanides.  Transition metal peroxide reactions

Vedejs, E.; Telschow, J. E.

doi:10.1021/jo00866a048

Cited by 37 publications

(1 citation statement)

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“…General synthetic methods for their preparation include the irradiation a-haloketones under microwave [12] or under a high-pressure mercury lamp condition [13], a-hydroxylation of an enolate with a molybdenum peroxide [14][15][16][17] or the other oxidizing agents [18], transformation of the enamine derivatives by molecular oxygen [19], metallic-catalyzed oxidative transformation of olefins [20][21][22][23] and hydroxylation of silyl enol ether with m-chloroperbenzoic acid [24,25] or with certain oxidizing agents [26,27]. Most of the synthetic methodology could not provide satisfactory reaction conditions due to the expensive and special instruments required or the expensive and dangerous heavy metal oxidizing agents needed.…”

Section: Introductionmentioning

confidence: 99%

An efficient and convenient transformation of α-haloketones to α-hydroxyketones using cesium formate

Wong

Chang

Lin

et al. 2009

Journal of Organometallic Chemistry

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Section: Introductionmentioning

confidence: 99%

An efficient and convenient transformation of α-haloketones to α-hydroxyketones using cesium formate

Wong

Chang

Lin

et al. 2009

Journal of Organometallic Chemistry

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Sulfonyl-Stabilized Allylic Norbornenyl and Norbornyl Carbanions: Structure and Stereoselectivity of Reaction with Electrophiles

Gais¹,

Gumpel

Raabe

et al. 1999

Eur. J. Org. Chem.

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The structures of the norbornenyl and norbornyl sulfones exo‐5, endo‐5 and endo‐6 have been determined experimentally, by X‐ray analysis, and theoretically by ab initio calculations (HF/6–31+G*). X‐ray crystal structure analyses of the lithiated allylic norbornenyl and norbornyl sulfones endo‐3/ent‐endo‐3·2diglyme and endo‐4/ent‐endo‐4·2diglyme revealed dimeric O–Li contact ion pairs devoid of C–Li bonds. The anions of endo‐3/ent‐endo‐3·2diglyme and endo‐4/ent‐endo‐4·2diglyme adopt both the endo conformation (C2–S) and are characterized by in the exo direction pyramidalized anionic C atoms. The degree of pyramidalization of the C2 atom of 3 is higher than that of 4. Ab initio optimizations (HF/6–31+G*) of the structures of the anions of methylenenorbornene I and methylenenorbornane II resulted in local minima featuring non‐planar C2 atoms which are pyramidalized in the exo direction in both cases, but to different degrees. In both cases cryoscopy of 3 and 4 in THF at –108.5 °C revealed approximately 1:1 mixtures of monomers and dimers. The sulfones exo‐5, endo‐5, exo‐6 and endo‐6 as well as the lithiosulfones 3 and 4 were studied by NMR spectroscopy. 1H‐NMR (400 MHz), 13C‐NMR (100 MHz) and 6Li‐NMR (44 MHz) spectroscopy of 3 and 4 at –100 °C in [D]8THF revealed in each case only one set of signals, independent of the configuration of the starting sulfones. This indicates in both cases that attainment of both the monomer‐dimer and the endo/exo equilibria of 3 and 4 is fast on the NMR time scale. According to 6Li{1H}‐ and 1H{1H}‐NOE experiments of 3 and 4 the monomeric and dimeric species endo‐3 and endo‐4, having endo anions, seem to be preferred in THF solution. Ab initio calculations of the anions of 3 and 4 resulted in structures endo‐3(–Li+), exo‐3(–Li+), endo‐4(–Li+) and exo‐4(–Li+) (HF/6–31+G*), whose atomic point charges were calculated by the method of Kollman et al. The C2 atoms of endo‐3(–Li+) and endo‐4(–Li+) are pyramidalized in the exo direction whereas the C2 atoms of exo‐3(–Li+) and exo‐4(–Li+) are pyramidalized in the endo direction. According to the calculations, the endo anions are more stable than the exo anions. There is good agreement between the optimized structures of the free anions and the experimentally determined structures of the anions of the contact ion pairs in the crystal. Reactions of 3 and 4 with DX, MeI, EtI, nPrI and nHeI occurred at the C2 atom under the selective formation of the corresponding endosulfones endo‐8a–e and endo‐9a–e, respectively, in all cases. Thus, an earlier report on the selective formation of the exosulfone exo‐9b in the reaction of 4 with MeI has to be revised. Product ratios were independent of the configuration of the starting sulfones and varied with the nature of the electrophile. Selectivities were highest in the case of the norbornyl species 4. Reaction of 3 with PhCHO occurred at the α position (C2) to afford the alcohols endo‐8f and exo‐8f (88:12) as single diastereomers and at higher temperatures at the γ position (C8), whereas reaction of ...

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Oxodiperoxymolybdenum(pyridine)(hexamethylphosphoric triamide)

Vedejs

2001

Encyclopedia of Reagents for Organic Synthesis

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Synthesis of cyanohydrins from cyanides. Transition metal peroxide reactions

Cited by 37 publications

References 1 publication

An efficient and convenient transformation of α-haloketones to α-hydroxyketones using cesium formate

An efficient and convenient transformation of α-haloketones to α-hydroxyketones using cesium formate

Sulfonyl-Stabilized Allylic Norbornenyl and Norbornyl Carbanions: Structure and Stereoselectivity of Reaction with Electrophiles

Oxodiperoxymolybdenum(pyridine)(hexamethylphosphoric triamide)

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