Fragrance raw materials monographs 287

p-tert-BUTYLDIHYDROCINNAMALDEHYDE

Synonym: Bourgeonal. CAS Registry No. 18127-01-0 CAS Index Name: benzenepropanal, 4-(1,1-dimethylethyl)-

Structure:

[CHa ] 3 . C . ~ CH2 .CH2" CHO

Description: A clear liquid. Occurrence: Has apparently not been reported to occur in nature. Preparation: From tert-butylbenzene and acrolein via a Friedel-Crafts alkylation. Physical properties:

Refractive index 1.510-1.511 Specific gravity 0.959-0.961

(Analytical data on the material as tested by RIFM.) Gas chromatogram and infra-red curve on file at RIFM.

Biological data

Acute toxicity. The acute oral LDs0 in rats was reported as 2.7 g/kg (2.16-3.38 g/kg) and the acute dermal LD50 in rabbits exceeded 5 g/kg with 1/6 deaths at that dose (Moreno, 1980).

Irritation. As part of an acute dermal LDs0 study, the undiluted material produced slight to severe irritant effects in rabbits patch-tested for 24 hr under occlusion at a dose of 5 g/kg (Moreno, 1980).

A 48-hr closed-patch test at a concentration of 6% in petrolatum on the backs of 29 volunteers produced no irritation (Epstein, 1980).

Sensitization. A maximization test (Kligrnan, 1966; Kligman & Epstein, 1975) was carried out on 29 volunteers. The material was tested at a concentration of 6% in petrolatum and produced no sensitization reactions (Epstein, 1980). This test concentration was based on a reported maximum concentration of 0.6% in consumer products.

References

Epstein, W. L. (1980). Report to RIFM, 25 June. Kligman, A. M. (1966). The identification of contact allergens by human assay. III. The maximization test. A procedure

for screening and rating contact sensitizers. J. invest. Derm. 47, 393. Kligman, A. M. & Epstein, W. (1975). Updating the maximization test for identifying contact allergens. Contact Dermatitis

1, 231. Moreno, O. M. (1980). Report to RIFM, 30 August.