68489-14-5Relevant articles and documents
Stereochemistry of the Menthyl Grignard Reagent: Generation, Composition, Dynamics, and Reactions with Electrophiles
Koller, Sebastian,Gatzka, Julia,Wong, Kit Ming,Altmann, Philipp J.,P?thig, Alexander,Hintermann, Lukas
, p. 15009 - 15028 (2019/01/03)
Menthyl Grignard reagent 1 from either menthyl chloride (2) or neomenthyl chloride (3) consists of menthylmagnesium chloride (1a), neomenthylmagnesium chloride (1b), trans-p-menthane (4), 2-menthene (8), 3-menthene (9), and Wurtz coupling products including symmetrical bimenthyl 13. The diastereomeric ratio 1a/1b was determined in situ by 13C NMR or after D2O quenching by 2H NMR analysis. Hydrolysis of the C-Mg bond proceeds with retention of configuration at C-1. The kinetic ratio 1a/1b from Grignard reagent generation (dr 59:41 at 50 °C in THF) is close to the thermodynamic ratio (56:44 at 50 °C in THF). Carboxylation of 1 at -78 °C separates diastereomers 1a/b to give the anion of menthanecarboxylic acid (19) from 1a, which combines with unreactive 1b to give neomenthylmagnesium menthanecarboxylate (1bI). The kinetics of epimerization for the menthyl/neomenthylmagnesium system was analyzed (ΔH? = 98.5 kJ/mol, ΔS? = -113 J/mol·K for 1bI → 1aI). Reactions of 1 with phosphorus electrophiles proceed stereoconvergently at C-1 of 1a/b to give predominantly menthyl-configured substitution products: PCl3 and 2 equiv of 1 give Men2PCl (6), which hydrolyzes to dimenthylphosphine P-oxide (7), whereas Ph2PCl with 1 equiv of 1 gave P-menthyldiphenylphosphine oxide (27) after workup in air.
N alkylcarbonyl amino lactone compounds and their use
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Page/Page column 10, (2012/07/28)
The present invention generally relates to refreshing, soothing, and cooling compounds that affect sensory processes. More particularly, the present invention pertains to certain N-alkylcarbonyl-amino lactone compounds as described herein; compositions and articles comprising such compounds; and methods of treatment, for example, methods of alleviating the discomforts of irritation, itch, and pain in the skin and in the linings of the oral cavity and upper respiratory tract, for example, in methods of treatment of cough.
PROCESS FOR MAKING NEO-ENRICHED p-MENTHANE COMPOUNDS
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Page/Page column 9, (2012/05/20)
A process for making neo-enriched p-menthane intermediates is disclosed. Lewis acid-catalyzed rearrangement of an oxaspiro compound provides an aldehyde mixture comprising normal (II) and neo (III) p-menthane-3-aldehydes: with the neo aldehyde (III) as the major product. The aldehyde mixture is readily oxidized to provide the corresponding carboxylic acids, and the acids are easily converted to a host of neo-enriched p-menthane esters or amides. The esters and amides are valuable as physiological coolants.