Geranium

Review problem 34 Design a synthesis for rose oxide, TM 307, a perfiime occuring in rose and geranium oils which is made at present by the oxidation of another natural product, citronellol. 

Many essential oils are used for flavoting and perfumery, eg, neroH, geranium, and ylang (see Oils, essential). The whole fmit, cmshed fmit, and puree may be used directly in foods, ice cream, cakes, and confections. Fmit juices, concentrates, and essences are more commonly employed (see Fruit juices). 

On ornamental plants CCC is appHed to a2aleas, geraniums, and hibiscus (Hibiscus sp] to make compact plants, and to poinsettias to reduce stem height and increase the red color of the bracts. A considerable amount of work has been carried out on cereals with CCC to reduce stem length and inhibit lodging. In Europe, the effect of CCC on shortening the culms of cereals is dependent upon the genotype. It has been demonstrated that the effect is as follows wheat > triticale > durum wheat > rye > oats > barley > corn = millet = rice (37). In barley, culms are initially inhibited but later the plant overcomes the inhibition (37). This has been attributed to poor assimilation, translocation, and rapid breakdown in wheat (38). 

Benzophenone. Benzophenone [119-61-9] (diphenyl ketone) exists in a stable form as colorless orthorhombic bisphenoidal prisms when crystallized from alcohol or ether. Other labile forms of lower melting point exist. Benzophenone has been identified as a flavor component of wine grapes and has a geranium-like odor. It is soluble in most organic solvents, and is insoluble in water. 

In 1961, chemists (19) isolated a minor component of geranium oil, characterized it as rose oxide (1), and reported that this compound contributed to the characteristic geranium odor. Rose oxide (1) is manufactured by the photooxidation of citroneUol (8). 

Part of the characteristic odor of geranium oil is described as peppery. In 1964, another trace constituent of the oil, furopelargone [1143-45-9,... 

Twenty-four years before its detection in nature PEA was first synthesized in 1876 (56) by reducing phenylacetaldehyde [122-78-1] with sodium amalgam. Then, in 1900, it was independently identified in otto of rose (57) and rose water (58). Subsequently, PEA has been identified in numerous flower oils such as ylang-ylang, narcissus, hyacinth, lily, neroH, and geranium as well as various other natural products like tea, tobacco, orange juice, beer, cigarette smoke, etc. 

Observable Characteristics - Physical State (as normally shipped) Liquid Color Colorless Odor. Weak geranium. 

Odors possess many classifications. There are 20 of them commonly used, all possessing rather picturesque names. In fact the names, in many cases, are far more pleasant than the odors themselves. To name a few of them - nasturtium, cucumber, geranium, fishy, pigpen, earthy, grassy and musty. Authorities further classify these odors in terms of their intensity from very faint, faint, distinct and decided... 

Determination of enantiomeric distribution of monoterpenoids from geranium oil... 

P Kreis and A. Mosandl, Chfral compounds of essential oils. Part XIII. Simultaneous chirality evaluation of geranium oil constituents , Flav. Fragr. 7. 8 161 -168 (1992). 

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