La acetate

Is / 4 la acetal or ketal. When the second alcohol is part of... 

To a solution of 4.2 g of lithium aluminum hydride in 420 ml of ether under a nitrogen atmosphere and cooled in a ice bath was added dropwise a solution of 99 g of tributyltin chloride in 210 ml of ether. The cooling bath was removed and stirring continued at ambient temperature for 1.5 hours. To the cooled solution was added 260 ml of water. The organic layer was washed with water and dried. This solution was added slowly at 15°C to a solution of (+)-2p,4p-dihydroxy-3a-iodo-5a-(methoxymethyl)cyclopentane-ip-acetic acid y-lactone 4-benzoate in 240 ml of benzene. Then the solution was evaporated and the product was stirred with water. Yield of (-)-3a,5a-dihydroxy-2p-(hydroxymethyl)cyclopentane-la-acetic acid y-lactone 3-benzoate 93%. 

To a solution of 0.20 g of (-)-3a,5a-dihydroxy-2p-(3-oxo-trans-l-octenyl) cyclopentane-la-acetic acid y-lactone 3-benzoate in 15 ml of tetrahydrofuran at -78°C under nitrogen was added dropwise 3 ml etheral solution 3 M methylmagnesium bromide. The solution became heterogeneous after 2 hours, to the mixture was added 10 ml of saturated aqueous ammonium chloride and then ether and water. Organic extract was washed with brine, dried over sodium sulfate, and evaporated to give 0.21 g of (-)-3a,5a-dihydroxy-2p-[(3RS)-3-hydroxy-3-methyl-trans-octenyl] cyclopentane-la-acetic acid y-lactone 3-benzoate as a colorless oil [a]D = -80° (c 1.0, CHCI3). 

Inoue and May(21) later modified the preceding synthesis with the presence of an 8-methoxyl substituent (Scheme 4.8). The key intermediate dihydronaphthalene (66) gave on treatment with mercuric acetate 8-methoxy-2,lla-dimethyl- la-hydroxybenzomorphan (67) in 49% yield, 5% of the 11/3-methyl isomer (69) and 13% of the la-acetate (68) corresponding to 67. Transformation to the desired 11-epimeric benzomorphans 70 and 71 was by standard methods. 

A stoichiometric solution of anhydrous La acetate (or acctylacetonate) and Al sec-butoxide in 2-methoxyethanol was refluxed at 125°C for 8 h, and hydrolyzed in a water-ethanol mixture. 

Fig. 14.12 Formation constants at 2S °C for 1 1 chelates of LnJ ions with various aminepoly-carboxylare ions (ida, iminodiacetatc nta, nitrilo-triacetate , N-hydroxy-eihylethylencdiaminetri-acetate edta. ethylene-diamincleiraacelate cdta. Irans-l, 2-cyclohexane-diamineietraacetate dtpa. diethylenetriaminepen la-acetate). [From Moeller, T. J. Ckem. Educ. 1970, 47, 417-430. Reproduced with permission.]...

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