The preparation of cyclopentadecanone and cyclopentadecanolide from Malania oleifera Chum oil

The macrocyclic musks are of central importance in the fragrance industry. The preparation of cyclopentadecanone and cyclopentadecanolide from Malania oleifera Chum oil were investigated. Preparation method of cyclopentadecanone is three steps process: first fatty acid double bonds of Malania oleifera Chum oil are cut off by ozonolysis; second ozonides are converted into methyl esters by esterification; afterwards cyclopentadecanone was achieved from through acyloin condensation, reduction and separation with 38.5 % overall yield. The preparation coyfclopentadecanolide is two step process: first by ozonolysis triglycerides of ω-hydroxycarboxylic acids synthesized from malania oleifera chum oil by ozonolysis; and it were catalytically transformed to macrocyctic lactones, and a 63% yield of cyclopentadecanolide was obtained. The effect of different ester groups on cyclization of α,ω-difatty acid alkyl ester, and effect of catalysts on cyclization of ω-hydroxycarboxylic acid triglyceride were investigated.


21
Cyclopentadecanolide and cyclopentadecanone are two important macrocyclic musk [1], and widely used 22 in perfumes, cosmetics, food, and medical. Cyclopentadecanolide exists in many plants [2, 3], but its content 23 is very low, this is difficult to extract and separate cyclopentadecanolide. Several preparation methods of 24 cyclopentadecanolide have been developed [4, 5, 6, 7]. Ookoshi [8] has been reported that the 25 macrolactonization of x-hydroxyalkanoic acid in a highly concentrated solution is catalyzed by dealuminated 26 HY zeolite. The HZSM-5 zeolite is one of the solid acids which have been widely used as viable alternatives 27 to conventional acids in esterification reactions [9, 10, 11]. Lai [12] has been reported that macrolactonization 28 of methyl 15-hydroxypentadecanoate to cyclopentadecanolide over Mo-Fe/HZSM-5 catalyst. The important 15-hydroxyalkanoic acid is complex and difficult when synthesized by chemical methods.

31
Cyclopentadecanone occurs, along with cyclopentadecanol in the secretion of the North American musk rat.

41
Therefore, the cost of cyclopentadecanolide is relatively high when 15-tetracosenoic acid is used as raw 42 material.

43
In the present work, the purpose is to make efficient use of natural plant resources, the preparation of

81
The reaction mixture was added to ice water, filtered and washed with water to obtain solid. The solid was dried 82 to give 30 g mixed products P1.

86
P2 30g in xylene (40 mL.) was added to pulverized sodium (10g.) in refluxing xylene (500 mL) under nitrogen 87 during 1 hr. The mixture was refluxed for 1 hr. Then, 150 mL ethanol was added slowly to the reactor at 80℃, xylene solution was separated from reaction mixture, and then treated with water. Xylene was evaporated under 90 reduced pressure. The residue was distilled to give 16.0 g acyloin.

91
Hydrochloric acid (16 mL) was added to the mixture of crude acyloin (16.0 g.) and Zn powder (4g) during 1 92 hr at 110℃. After the reaction maintained for another 30 min, the mixture was cooled to room temperature, 93 extracted with benzene (200 mL), and washed with water.

94
The mixture was distilled, separated by vacuum distillation (or vacuum distillation of glycerin as entrainer)

95
and recrystalled with ethanol to obtain cyclopentadecanone 16.0g with purity of 97.4%. 100 aqueous solution at 10 ℃ for 3 hr. Then neutralize to neutrality with hydrochloric acid for 2 hr, filtration, 101 washing with water for 3 times, and drying to obtain ω-hydroxycarboxylic acid triglyceride 135 g.

102
Put ω-hydroxycarboxylic acid triglyceride (5) (100 g) and catalyst into 1000 mL three bottles, then slowly 103 add glycerol and heating up to make glycerol distillate at vacuum degree is <755 mmHg, and mixture products  116 The production costs of MeOOC(CH 2 ) 13 COOMe or HOOC(CH 2 ) 13 COOH are high, in the preparation of 117 cyclopentadecanone. Interestingly, the content of 15-tetracosenoic acid is 46.7 % in Malania oleifera Chum oil,

118
it is a good raw material for preparing cyclopentadecanone. In this paper, preparation of the cyclopentadecanone from Malania oleifera Chum oil was described and displayed in the figure 2.  Table 1. 131

149
Afterwards, the desired product cyclopentadecanolide with 63 % overall yield was achieved from mixed 150 ω-hydroxycarboxylic acid triglyceride through cyclization and separation. This is a very short technological 151 route, and it is easy to industrialize.

152
Comparing the prepared cyclopentadecanolide with the standard cyclopentadecanolide, IR (KBr), GC-MS, 1 Table 2 shows that the yield of cyclopentadecanolide is 63% when using mixed catalyst CH 3 ONa/ NaOH, it is 161 high compared with catalyst single NaOH or CH 3 ONa. This synthetic route is short and has the value of