University:
University of Virginia
Course:
CHEM 2410 | Organic Chemistry I
Academic year:

2024
Views:

282

Pages:

2
Author:

Kayli N.

Curved Arrows : drawing resonance "Flow of - - where ↳ where electrons elections are structures , treats electrons coming from ex would breaking exceed . Never 2 · but a single bond [changes : a eX bond single can be * elements Carbon would have 5 bonds ex - VI # has broken 3 :: . s carbon doesrid have octet bonds: can receive electron curved Arrow can cancel second , become structures octet can have less than T second-row octet for ex Not 1. . X Avoid . to out violation C i I &C - 1 9 V Not + It H single bond & tail moving were they going are Rules : 1 if as electrons" X exceeds octet C Formal ex charges 6 5 - 00 = 1 C - .- Resonance cannot change lone + I localized pi bond = localized n H is)N : allylic it bond to NOT resonance = , geometry (eX . NOT allylic to * S of = sp2 localized bond delocalization I atom Is affected ex IN . Only band electrons of of individual by lone lone resulance structures) pair has both lone pair ex. resonance + i bond pair lone pair NOT - I (double) already bond spabent (combination - in called Delucalized It has partial charges represent Spesp2) it sp3 trigonal pyramidial : W next to it bond LP St I n resonance : - IP occupies p orbital = hybridization pairs i No = delocalized Hybrid Delocalized lone pairs localized H C H - Trigonal planar EX · 2X allylic to it bond ⑦ (* Ex 0 : Not valid resonance structure Drawing 1. Resonance Allylic Lone = al structures C C in is a d = a Allylic Position Atoms allylic 3have e cC position connected to C=C ↳ · - Conjugated c - to I curve arrows positive charge moved to can push . A lone pair 3 : % cancels o of positive I bod a on change , XX tail lone pair goes from head to form it bond (double bond) ↓. add another arrow to work charges differing electronegativity :: & & # bonds : A > : * system to C · bin 2 atoms Conjugated eX by + Adjacent i It bond a other end of separated place curved arrow fail never z , but one at a time j. ↳ I bonds : required only I curved arrow . 5 - Not vinylic = 4. Recognition Allylic Carbocation . 2 4 Pattern Pair vinylic = via moved it (double) onto to enclosed In # 1 -in s bond electronegative atom . 2 form a lone pair . 3 ring push - all it bonds Clockwise or overI position counterclockwise Fewer formal charges O on more x electronegative +X i St (more) St