2- methoxyphenyl isocyanate

C8H7CI03 4-chloro-o-anisic acid 57479-70-6 522.15 46.016 2 13145 C8H7N02 4-methoxyphenyl isocyanate 5416-93-3 448.00 38.911 2... 

Previous preparations by Scolastico were based on the Strecker synthesis of aminonitrile and lacked steroselectivity [74,75]. More recently, two formal syntheses were reported from the same ketone 71. In Rama Rao s synthesis (Scheme 11.19) [76], 71 was condensed with vinyl magnesium bromide to give the tertiary alcohol 72 as a single isomer. This compound was then transformed into the vinyl epoxide 73 that, under palladium catalysis, reacted with 4-methoxyphenyl isocyanate to produce the oxazohdinone 74 with retention of its configuration. The remainder of the synthesis consisted of heterocycle opening and adjustment of the oxidation level to provide the lactone 75. Excision of two carbons was necessary to form the known aldehyde 76, previously transformed into myriocin [74]. 

This sequence has been used for the synthesis of 6-methoxymurrayanine (232) (Scheme 55) [214]. Reaction of butane-2,3-dione (226) with 4-methoxyphenyl isocyanate (227) to 4,5-dimethylene-3-(4-methoxyphenyl)-l,3-oxazolidin-2-one (228) followed by regioselective boron trifluoride-catalyzed Diels-Alder reaction with acrolein afforded the oxazolone 229. Only minor amounts of the undesired regioisomer were formed. Aromatization using 2,3-dichloro-5,6-dicyano-l,4-benzoquinone (DDQ) afforded the benzoxazol-2-one 230. Saponification of the cyclic carbamate and subsequent O-methylation led to the diarylamine 231. Finally, oxidative cyclization using stoichiometric amounts of palladium(ll) acetate provided 6-methoxymurrayanine (232). 

A suspension of 8-hydroxyquinoline 652 (1.45 g, 10 mmol) and 4-methoxyphenyl isocyanate (1.49 g, 10 mmol) in diethyl ether (100 mL) was stirred for 2 days at room temperature. The precipitate obtained was collected by filtration and crystallized from diethyl ether/acetone to give 1.9 g (65% yield) of product 653 mp 129-130 °C. 

Afferent behaviour is observed with poly(4-methylphenyl isocyanate) and poly-(4-methoxyphenyl isocyanate) which is consistent with a much greater coil flexibility for these phenyl substituted polyisocyanates A... 

Methoxyphenyl)ethanone 2-(4-Methoxyphenyl)-1W-indene-1.3(2W)-dione 4-Methoxyphenyl isocyanate... 

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