April 20, 1050
CO\INUNIC.\TIONS TO
TIIB EDITOR
2027
animal nutrition, particularly in chicks, prompted acidic reagents, we have found that 2-osa-1,2dihydro-cizdo-dicyclopeiitadielie1-3 (11) resists the us t o examine the plant quinone. Extraction of commercial alfalfa nieal with rearrangement t o the cso-configuration characpetroleum ether followed by chromatography on teristic of its hydrocarbon analog.' Stabilization Florisil and on Decalso yielded a crystalline yellow of the initial carbmium ion bv the 2-oxa atom is 'I'he = 217 proposed t o explain the anomalous beha\.ior. quinone, m.p. 4S-49°.9 Ultraviolet: at 254 mM and 2% at 2G2 mfi in isoijctane. Reduc- steric possibility of such participation is proved by tion with sodium borohydride gave t h e hydroqui- cyclization of 2-aza-l,2-dihydro-endo-dicyclopentadiene (111) with hydrobroniic acid (4S5-A) followed none: = 48 a t 290 mp in ethanol. The infrared spectrum in carbon disulfide differs from t h s t by 23\70 sodiuni hyclrouide yielding the tertiary of coenzynie Qlo niainly in t h e absence of the in- amine IV, the first nieniber of a new heterocyclic tense i . S fi band associated with the methoxyl ring system. .hiitic 1V is identical with structure V. function ; all other functional bands are similar. The n.m.r. spectra'" of I and its side-chain reduction product and of 2,3-dimethyl-5-farnesylbenzoquinone (11) and its side-chain reduction product when interpreted in coinparistin with the spectrum of QltI1lled to structure I for alfalfa quinone. I t shows a ring proton as a triplet a t 4.5, G, and 7 c.11.s. aiid no metlioxy protons. The latter are replaced by ring CH3-functions which show a t 1'7s C.P.S. in the side-chain reduction product which I I1 Ill does not have the interference caused by the =C-CH2-CH2-C-= functions. T h e fact t h a t the ring proton is a triplet and not a quartet significs t h a t its ortho group is the side-chain - C H r and nut CHa--. Since the ring methyl protons are not spin-coupled, no ring proton is ortho to them. The ratio of the area of the doublet a t 131, 141 C.P.S. to the ring proton triplet is 2 t o 1. Thus, only one long side-chain is present ortho to the ring prc'tori, and the two ring CHa- are ortho t o each other. This is confirrned by the G to 1 area IV V VI ratio of the ring CHa- resonance (1'7s c.p.s.) to the The secondary amine I11 (iii.p. 117-110" with riiig protoil resoiiance in the quinone reduction product. A11 these tleductioris are quantitatively sublimation a t about 55". Calcd. for CgH13N: supportetl by the ri.ii1.r. spectra of %,3-diniethyl-3- C , T9.93; H, 9.69. Found: C, "3%; €1, !I.Sl), famesyl-1,Lbenzoyuiiioiie aiid its side-chain re- prepared by lithium aluniinuin hydride reduction of endo-bicyclo[2.2.1]-3-heptene-2,3-dicarboxylicacid duction product. forms an 2,:~-~iiiicth~l-3-farnesvlbciizo~luirioiic (11) was imide"-7 by the method of Rice, et alkali insoluble benzenesulfonamide (m.p. 107synthesized from 2,:3-diiiicth!lli\idrocluiiio~ie and fariiesol as a yellow oil; a n d . Found: C, S1.39; 10s". Calcd. for CI5H1;NSO2:C, G5.42; H, (3.22. H, 9.22; ultralriolet iii isoiictarie, EM = 1S,OO0 a t Found: C, G3.2(i; H, G X ) , and is reduced readily 233 i i i ~ ,ant1 15,SOO a t 261 m u . Coiiibiiiirig this by catalytic hydrogenation t o the saturated amine, with the ultraviolet data of the alfalfa quinone isolated as the beiizciic.sulfonamidc ( 1 n . p 168l(iS.5". Calctl. for C15HIt,KSO~: C, G1.95; H, leatls t o ;t value of 9 for 11 in I. (3.00. Found: C , G1.W; 11, G.7G). The tertiary (9) Cr;inc's Q-224 a n d uiir (,'tinone were 1101 wparate(l on amine IV (n1.p. 126-128" with sublimation a t iiiiprcxiiate
