Question

Select the eight compounds below that are expected to exhibit aromatic stabilization. Note that lone pairs have not been shown - their presence or absence has to be inferred from the number of bonds and the formal charge (if any). Assume that the system can achieve planarity if needed for aromaticity. Note - higher partial credit could be achieved by selecting less than eight of them if you are unsure on some of them. MeN-Me Me-N N-Me "Me 8.26. Me 3.8.0.0 Me Me N Me-N Me Me Me Me ӨН -N-N. MeN-N. Me

Answer 1

Ans: For a Compound to be anomalie", following format Conditions foro Cromatic Stabilisation de no (i) The compound must be cyclic, planars, each coton in the ming contains atleast one unhybridised p-orbital. Balleries cü Fully Conjugated system and follow the Int2]ales . System - Huckelimele 920,1,2,.... eg. A o aromatic system ao follow (Ant2Jxe's neile Due to the participation of one lone pain of oxygen's pratomic Orbital, the 5-memben furan ring get aromatic stabilisation 4042 anal ; *4.1+2) a tres in furansing. cle A Me N N the Aftero Contatting the considering the e two lone pains of electron on two nitrogen p-atomic orbital the cyclic ring contains total lotes i.e, obey the Huckel's nule (Ant2ltés where = 2 . It is anomatic in nature.

= ON a Here the 6-membero mring Containing two positionally charged N'atoms have the Gresso it also follow (4n+2)te's Here nah, therefore it also has anomatic stabilisation. f. s m Total ming contains Itine's, theus be e Sharing the tes among the ring - the system follows (Ant2/he's rule where nag. Theis compound gets aromatic Stabilisation. 2. Mean y participating the lone pairs of ? electron on N'atoms and sharing the Télectrons each fused five members bypoole bring satisfies (4n+2) te pule, nal and a total 10.kes in the two sing. This the compound is aromatic in nature de TK). B. Bhas a vacent prenbit al perspendicular . to the three members molecular He le plane this it can take part in Conjugation of the two relectroms. In this way the totally conjugated System Satisfies (Ant2)te's

roule. (An+27 ; n20 : 2te's Theo the get Compound gets aromatic Sotabilisation). Apparently the compound hab She's it but if the Lone pairs on conkeyboridised .. p-orbital of s' takes part en in Conjugation with the fie's then it will be aromatic, as in this way it satisfies (A112)ães male where ne 2 lie, la conjugated 10tes in the System. Rattano compends : I can identify these Seven Compounds should be aromatic stabilised. Other compounds like - 4 all 5 3 hybmdised saturated Carbon present, not fully conjugated . hence non-aromatic al this positively charged it has no cinhybridised prombital foro y conjugation hence non-aromatic

- G. of laste's 1.c, Anie's 3 naba ther does not follow the aromatic electron court rule actually His ante anti aromatic in nature due to satisfy ant'se mule. A. O total Sie's System; the's in - each ming Yanti omomatic. 2aes total, The's in eachroring 1 1 => arsti Qoromatic Compound. A may non aromatic but the middle Spa ce does not involve in Conjugation. L a Ares (considering lone pairsonal) The => Anhe's not ... antiarsomatic compound. I though it has lone pairs of es but Nema conjugattow is not possible HNon omomatic ace

WA Elen Ste's antiomomatic Anto's 1, 2 90.000 até odlicansmatic. ชร เv| nal