CHB-CH-CHI

Ar

CHB-CH=CH2 + HBr 2-bromopropane

C&-CHz-CH2-Br

l-broinopropane

CH 423 215

216 CH 423

VllTlJd 10.1 Apparent degree of dissociation (‘70) WI9 methyl-substituted “hexaphenylethanes”

0.1 M solution in benzene (To1 = CH3C6H4)

“(PhzTolC-):) ~ “(PhTolsC-):’ “(TolsC-):-

meta-To1 6.5 I 40

para-To1 5 5.5 1 6

(nuclear magnetic resonance (n.m.r.) spectrum)

Zn

PhsC-Cl -F PhsC* -+ Ph&-CPh,

X

(2) (3)

n"7lh hexaphenylethane WIU (1) ttzl”a I3lfl35l~U aromatic protons tViI&U

ILdtYl^ILh (2) ISlOZlTh aromatic protons 1111E olefinic protons n”afJ ~d~l~~a'llihJYnlY

~l¶JfI3dl-?n"ju' REiU dimerization ~~~6Fl'illflfll5~ triphenylmethyl redical W~J1hV!l

CH 423 217

Initiating reaction + F’

F. + CH4F2

+ HF+CH;- CH3F + F’

F1F’+CH,F + HF+CH,F’- CH2F2+F

F2F +CHzFz - HF+CHF;- CHF3 + F’

F’ + CHF, F2+ HF+CF; - CF,+ F’

218 CH 423

10.1 Stereochemistry

H ,,,,W”’ c -

/ b.,CHKH,

.I + OH- F HO-C L,-,’

\+ I-

r”,CfI,

CH 423 219

SO&H&HI

IPhCHz 0 K&OJC2H50H PhCH2 H

\c/ - lc/

/\ (b) /\CH3 H CHJ (3235

t-1

PhCHz OH

’ c’/ \

CHJ H

(+)

\_

K

(4)03

220 CH 423

(- )- CH,-CH-CO;

$lH

SJ inversion

(+ )-CHJ -

+T-( + )- CH,-CH-CO;

CHs HI

S,l retention

OH

(6)

CH 423 221

C& CH3\ /HAc=c\, + Br2

22? C!H 423

I + NH; -

CH-423 223

Benzyne

224 CH 423

‘bI

+ CzHs ‘%H

/ 1 Ha0 /,C2H5 -

c\

> W-b- c + C3HSO’H (14)

0

OH

CH 423 225

1. “lug fl.fl.1920 !~d@?flMld@s‘Ul ring closure v89 cyclopropane rings

x\c$c - x\ 7/\x c X

/c\c

R\C/CO-C03H OH

OH‘

R/\ =

COzH

CHrC02HCOIH

(1) (2)

2. I&Id1 2-bromo-Snitroacetophenone IJNdU¶J oxime ‘SE%@72 geometric isomers (A) LlW

tion

226 CH 423

H, NO,N ’

as:.. H,SO, 93 ‘5,: 0% 7 :/,

NH,

0I>

HNO,85X H,SO. 6% 34;/, 59%

CH 423 227