N(C(OCC)=O)=NC(OCC)=O.C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1.[CH3:32][C:33]1[O:34][C:35]([CH:38](O)[CH2:39][CH3:40])=[CH:36][CH:37]=1.[OH:42][C:43]1[C:50]([CH3:51])=[CH:49][C:46]([C:47]#[N:48])=[CH:45][C:44]=1[CH3:52]>C(Cl)Cl>[CH3:32][C:33]1[O:34][C:35]([CH2:38][CH2:39][CH2:40][O:42][C:43]2[C:50]([CH3:51])=[CH:49][C:46]([C:47]#[N:48])=[CH:45][C:44]=2[CH3:52])=[CH:36][CH:37]=1Diethyl azodicarboxylate (DEAD, 11.9 mL; 75.6 mmol) was added dropwise over a 10 min period to a solution of triphenylphosphine (19.8 g; 75.6 mmol), (2-methyl-5-furanyl)propanol (ex 1a, 9c and 12a) (10.6 g; 75.6 mmol), and 4-hydroxy-3,5-dimethyl-benzonitrile (12.2 g; 83.2 mmol) in methylene chloride cooled in an ice-bath under nitrogen with stirring. After 10 min, a solid formed. Additional methylene chloride (50 mL) was added to the mixture and the resulting suspension was filtered. The filtrate was washed with water (2×100 mL) and brine (1×100 mL). The organic layer was dried over anhydrous magnesium sulfate, and concentrated in vacuo to yield a brown oil which crystallized on standing. The solid product was chromatographed on silica gel eluting with ethyl acetate/hexane (2:8), and the appropriate fractions were concentrated in vacuo to afford 16.43 g (81%) of 2-methyl-5-[3-(2,6-dimethyl-4-cyanophenoxy)-propyl)furan. The cyano moiety is then elaborated to a suitably substituted 5-tetrazolyl moiety as in the preparation of Intermediates 5-6 or oxadiazolyl as in Intermediates 7-8, giving a compound of formula II wherein R3 is methyl, R4 is hydrogen, R1, R2 is 3,5-dimethyl Y is 1,3-propylene and R5 is as described.
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