[化] 烯丙位取代(取代在邻接于双键的C上)

allylic substitution的用法和样例:

例句

  1. That is encouraging for palladium-catalyzed allylic substitution reactions which is difficult to use in industry due to the current low reactivity of catalysts.而且,值得注意的是这类配体的反应活性都非常高,对于由于催化剂活性低难以在工业上应用的钯催化烯丙基取代反应来说,这无疑是一大喜讯。
  2. There were few successful examples of regioselectivity in reactions of unsymmetrically allylic derivatives, and enantioselectivities obtained with prochiral nucleophiles.因而我们选用反应机理相对比较清楚的钯催化烯丙基取代反应来研究平面手性的作用。

应用修辞是让我们的语言更富于形象性,当我们运用不同的词汇,不管高级还是低级,修辞的运用将会比普通的词汇更有文学层面上的意义,从修辞中我们可以增加想要说明的效果,创造更有

发表于:2018-12-08 / 阅读(45) / 评论(0) 分类 GRE英语

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发表于:2019-02-01 / 阅读(47) / 评论(0) 分类 GRE英语

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发表于:2019-02-01 / 阅读(47) / 评论(0) 分类 英文语法词汇

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发表于:2019-02-18 / 阅读(43) / 评论(0) 分类 GRE作文

cramp sb.'s style妨碍某人 high style女装的新款式 in style别具风格的 in the style of仿…式样 like [as if] it's going out of style (fashion)不值钱 live in style过上豪华生活 o

发表于:2019-02-18 / 阅读(56) / 评论(0) 分类 考研英语

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发表于:2019-02-19 / 阅读(37) / 评论(0) 分类 GRE作文
学英语单词
airborne computer
aircraft boresight reference line
alar ligament (or check ligament)
apollo programs
asyndetus mutatus
at-a-glances
be all over
bitts
bridge-balanced d.c. amplifier
busting out
candidia pingtungensis
chalcedonica
chemogenic reaction
codominant tree
commercial aeroplane
concoct
contribution fee
convergent factor
copurification
cosmetically
disagreements
disarmed interrupt
drive - in restaurant
erry
erub
extra slim hole
Ferrier Peninsula
fetal electronic monitoring
fibrement
filthifying
friedel-crafts alkylation
fuze jammer
g distribution
gas explosion tube
gear segment
glass-bottoms
Gobind Singh
half absorption value
haplotypes
insurance-relateds
Jakha
jerries
job control record
just bias
lashing materials
lay chase
lequire
liver plate
low-level laboratory
machine rate method
mechanical suspension
military metaphor
moment of strength
monumental inscription
multiprogramming despatching
musickes
n.v.
naristilla
outer wheel hub
ovariectomies
oxygen-acetylene welding
Pacific daylight saving time
participatory
pico-katals
placenta nappiformis
planished steel sheet
plearoclysis
Predsolan
quarter phase system
radiant heat test
radiofrequency polarography
rags-to-riches
right of execution
Schuttertal
sebiolith
sethos
shark bait
shoot through with
shortening heat
singular quadric
skin hard
spanish-tile
Stellaria uliginosa
stress rupture testing machine
subscription fee
tank feed auger
tear jerkers
teinter
the call of
the continental brack hypothesis
the Metropolitan Police
tip-tilt
togs
tracer tools
transition belt
undret
unprofessing
unranged
VWO (valve wide open)
weaner ill-thrift
write bias