The Reduction of Some Phthalamic Acids with Lithium Aluminum Hydride

The phthalamic acids II and VII derived from 2-phthalimidooctadecane (I) and (-)-2-phthalimido-3-octadecanone (VI) were submitted to reduction with lithium aluminum hydride. The reduction of II afforded two products, i. e. 2-(o-hydroxymethylbenzamido)-octadecane (III) and 2-(o-hydroxymethylbenzylamino)-octadecane(IV). By reduction of VII only 2-(o-hydroxymethylbenzamido)-3-octadecanol (VIII) was obtained. When hydrolyzed III and VIII yielded, after subsequent acylation, 2-acetamidooctadecane (V) and 2-benzami do-3-hydroxyoctadecane (IX), respectively. The hydrogenolysis of IV afforded V. These reactions may present an alternative method for the elimination of the phthaloyl group

Interactions in Carbocations and Huckel\u27s 4n + 2 Rule

The molecular orbital model of hyperconjugation was utilized in rationalizing some long range interactions in carbocations. Conveniently such interactions can be detected by measuring secondary · kinetic deuterium isotope effects. Hilckel\u27s 4n + 2 rule can be extended to interactions between the cationic center and pseudo-:n: orbitals of CH3, CH2 and CH groups respectively. Thus, in analogy to hyperconjugation one can envisage homohyperconjugation as the probable cause of normal y-deuterium isotope effects. Results are presented of studies of these effects in the adamantane and norbornane system. The stability of the 1-adamantyl cation can be ascribed to a favorable 4n + 2 configuration of a-electrons comprising the ~,y-carbon carbon and/or y-carbon hydrogen bonds. It is however not possible to distinguish between these alternatives since both could explain the observed y-isotope effects. In contrast, the four CH2 groups flanking C7 in the 7-norbornyl cation form an antiaromatic 4n pseudo-:n: system which could explain the exceptional instability of this cation. Interactions of the empty p-orbital with the subjacent 4B2 pseudo-:n: orbitals give rise to small normal y-deuterium isotope effects of homohyperconjugative origin. In this system, due to symmetry constraints hyperconjugative interaction with the ribbon orbitals of the a-framework is not possible

2-Hexadecynoic Acid

The hitherto undescribed 2-hexadecynoic acid (III) was prepared by the following route. Dodecylmagnesium bromide was reacted with 2,3-dibromopropene to give 2~:bromop e ntadecene (I) in 35 % yield. Refluxing the bromo compound I with freshly prepared sodium amide in xylene gave pentadecyne(II) in 49 .1 % yiel

A Synthesis of DL-a-Amino-B-hydroxy-valeric Acid. (Hydroxynorvaline)

By applying the method used by Pfister et al. for the synthesis of threonine we prepared DL-a-amino-B-hydroxy-valeric acid (hydroxynorvaline) starting from ethyl B-keto-valerate. This amino acid was prepared earlier by different methods by Osterberg , Abderhalden and Heyns , Botviillii.k et al, Euston et al., and by Izumiya. The melting points of hydorxynorvaline and of its N-benzoyl derivate indicate that the product obtained consists mainly of the threo-isomer

On the Reaction of α-Phthalimidoacid Chlorides with Substituted Sodiomalonates. A Method for the Preparation of α-Amino Ketone s and Related Compounds

The Bowman ketone synthesis was successfully applied to N-phthalylaminoacid chlorides. Inthis manner 1-phthalimido-4-phenyl-2-butanone [V] as well as 1-phthalimido-2-octadecanone [IV] were formed in the reaction of N-phthalylglycyl chloride with corresponding substituted dibenzyl or ditetrahydropyranyl sodiomalonates. The optically active 2-phthalimido-5-phenyl-3-pentanone [X] was obtained with N-phthalylalanyl chloride. From 1-phthalimido-4-phenyl-2-butanone [V] we prepared 1-benzamido-4-phenyl-2-butanone [VII] and 1-amino-4-phenylbutane [IX] so that the reaction represents a method for the preparation of a - amino ketones and related compounds

2-Hexadecynoic Acid

The hitherto undescribed 2-hexadecynoic acid (III) was prepared by the following route. Dodecylmagnesium bromide was reacted with 2,3-dibromopropene to give 2~:bromop e ntadecene (I) in 35 % yield. Refluxing the bromo compound I with freshly prepared sodium amide in xylene gave pentadecyne(II) in 49 .1 % yiel