Neopentyl alcohol system

With the exception of neopentyl alcohol (mp 53°C), the amyl alcohols are clear, colorless Hquids under atmospheric conditions, with characteristic, slightly pungent and penetrating odors. They have relatively higher boiling poiats than ketonic or hydrocarbon counterparts and are considered iatermediate boiling solvents for coating systems (Table 1) (1—16). 

In the zeolite-promoted benzylation, however, it was observed that the reactivities of the alcohols decreased in the order 1-decanol > benzyl alcohol as cyclohexylmethanol a neopentyl alcohol 1-adamantylmethanol. The adsorption isotherms for the alcohols on zeolite KY in benzene show that even the most bulky 1-adamantylmethanol can be adsorbed inside the cavities of KY as readily as 1-decanol (Fig. 2). Hence the low conversion of 1-adamantylmethanol in the KY system can be ascribed to steric hindrance in the transition state the alcohol is so bulky that it is relatively difficult for the alcohol to be oriented in close proximity to a benzyl chloride molecule between acidic and basic sites of the zeolite. 

Myristyl propionate Neopentyl glycol dicaprylate/dicaprate Neopentyl glycol diheptanoate Octyl palmitate Passionflower (Passiflora incamata) oil PEG-75 lanolin PPG-14 butyl ether PPG-5-ceteth-20 PPG-50 oleyl ether Stearoxy dimethicone Stearoxytrimethylsilane emollient, aq. alcoholic systems Diisopropyl adipate PPG-5-ceteth-20 emollient, aq. compositions PPG-12-PEG-50 lanolin emollient, aq. lubricants PEG-150 distearate emollient, aq. paints PEG-150 distearate emollient, baby care Acetylated lanolin alcohol emollient, baby powders Potato (Solanum tuberosum) starch Rice (Oryza sativa) starch emollient, baby preps. 

Rawal applied the Poulter procedure in the total synthesis of pederin, an example that also highlights the power of the Curtius rearrangement for installation of an acyclic hemiaminal. Saponification of a-methoxyester 81 and DPPA-mediated acyl azide formation led to rearranged iV-acyl hemiaminal 82, a strategy pioneered by Roush and Matron in their approach to the structurally closely related mycalamide and onnamide systems. In the Rawal example, the reaction occurred smoothly in the presence of a free neopentyl alcohol group at Cl3. 

The SNl-type process occurs mostly when B is a tertiary atom or has one aryl group and at least one other alkyl or aryl group. In other cases, the SN2-type process is more likely. Inversion of configuration (indicating an SN2-type process) has been shown for a neopentyl substrate by the use of the chiral neopentyl-l-d alcohol.18 On the other hand, there is other evidence that neopentyl systems undergo rearrangement by a carbocation (SNl-type) mechanism.19... 

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