dnced in situ by tho interaction of limo niid sodium cnrlionntc. I n this i ~n y undesirnblo subsidinry renctions, wliicli occur wlicn escess of frcc nlknli IS present, nre nvoidctl.
(c) Aiiisidiiic.-'l'ho reduction of o-nitronnisol is c n r r i d out 11s ine:ins of zinc powder iind wiiter. Tho reduction procecds nioro quickly in tho prcseneo of cnlcium cliloritlo (I)ainbergcr's process), aiid discoloration niicl fornintion of di-nnisidine, such ns occur when iron nnd ligdrochloric ncid nro cniployed, nro nroidecl. Tho nitronnisol is nddcd to n solntioii of cnlciuin clilorido in tlio ninount of w t e r tlieoreticnlly rcqnired for tho retlnction, nnd tho zinc powder is slowly nddccl to tlio boiling solution. After cooling, the rcduced product is extrncted witli h i i 7 . 1 1 ~. /so* / S I 1, ' '\OCโฌI, + 3%n+411,0=C I1 + 3 Z n (OIi), c 11 ' 4\ocII, (u) Ditrzotisniion and Ctrrriucol I"orniution.-llio dinzotisntion is cnsily eficcted in tho ordiiinry innnncr, tho ronction bein followed by nie:iiis of 1 4 stnrcli-iodiclo J J pnper. l!io u~iminntion of frco nitrorren and tliu fornintion of crinincol Droceed Tlio trnnsformstions offcctcd in tho production c,f vanillin from phenol mny bo represented, thereforc, ns follows:-Tho economical ntilisntion of tlio rntlior complex Ecories of rcnctions hcniiio possiblo during tho wnr on ncconnt of tho risc in rico of tho rnnillin produced from e!igenol, w l i d was used for new urposcfi, c.y., in g ' d o p e s ~~ for neroplnnes, n n f so Imnino scarce. Tlio fnturo of syntliotic methods dcpends niniiily upon tho clicapness of tho originnl raw rnaterinls. If o-nitrophenol cnn bo obtained n t prices tlint ruled durinF somo pcriods of tho war, tho full synthesis of vnnilliii sltoulcl be conimorcinlly Irncticnblo, oven in conipctitioii with tho betternowi and proved iiictliods wliicli usc eugenol ns tlio stnrting mntcrinl. (E) Inlrodiiriioir 01 ihe rlltlcltytlc Croup into Cutiiticol.-\lien n mistiirc of gu:iincol, forinnlcle-