3,4-dihydro-2H-pyran → trans-6-Hydroxymethyl-2-methoxytetrahydropyran

HRID 466269

反応式

HRID 466269 の反応式
O1C=CCCC1.[CH3:7][O:8][CH:9]1[CH:14]=[CH:13][CH2:12][CH:11]([C:15](OC)=[O:16])[O:10]1.[H-].[Al+3].[Li+].[H-].[H-].[H-]>CO.Cl.C(OCC)C.[Pt](=O)=O>[OH:16][CH2:15][C@@H:11]1[O:10][C@@H:9]([O:8][CH3:7])[CH2:14][CH2:13][CH2:12]1

参加物

8

反応物 3

HCID 80803,4-dihydro-2H-pyranHCID 5572662H-Pyran-2-carboxylic acid, 3,6-dihydro-6-methoxy-, methyl esterHCID 21226445Aluminium lithium hydride

生成物 1

HCID 13108355trans-6-Hydroxymethyl-2-methoxytetrahydropyran

試薬・触媒・溶媒 4

HCID 313Hydrochloric Acid触媒HCID 345198Adams' catalyst触媒HCID 887Methanol溶媒2 回HCID 3283Diethyl Ether溶媒

実験手順

The absolute configuration for the product was determined by first isomerizing the dihydropyran derivative product in methanol by use of hydrochloric acid as a catalyst so that the product had a trans-isomer content of 95%, subsequently converting the ester into an alcohol in diethyl ether by use of lithium aluminum hydride, and then hydrogenating the double bonds by using platinum dioxide in methanol to give trans-6-hydroxymethyl-2-methoxytetrahydropyran, followed by optical rotation measurement. As a result, the optical rotation [α]20 of the above compound was found to be -119.9° (c=1.07, solvent: benzene). This found value was compared with the optical rotation [α]20 of +129.7° (c=4.3, solvent: benzene) for (2S,6S)-6-hydroxymethyl-2-methoxy-3,4,5,6-tetrahydropyran as described in J. Jurczak et al., J. Chem. Soc., Chem. Commun., pp. 540-542 (1983). Based on the comparison, the trans-isomer and cis-isomer were judged to be a (2R,6R)-isomer and a (2S,6R)-isomer, respectively.

出典と根拠

ORDレコード
ord-015bccbdc4b14c03a46a0c18658a7ee9
出典データセット
uspto-grants-1992_10
特許番号
US05155240

関連ノート

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