j*********5
发帖数: 6221 | 1 我做过酚的ullman coupling，用的是DMF作溶剂，CuBr做催化剂，产率70-80左右，单
一产品，不用过柱子
我觉得你为啥非得用这个溶剂，换个别的溶剂试试啊
ester。 |
|
A*******l
发帖数: 67 | 2 这个酯化有可能是Cu catalyzed吗？
ester。 |
|
|
d*******g
发帖数: 3972 | 4 try Trimethylsilyl ethyl ester as protection group, and deprotect with
fluoride |
|
r**x
发帖数: 408 | 5 这个LABEL起来不如那些succinimidyl ester方便啊，不明白是怎么LABEL上去的。 |
|
m********3
发帖数: 2125 | 6 这个有succinimidyl ester 版本的，不过不在市场上。
看下面的参考文献。
Neuron, Vol. 37, 85–97, January 9, 2003, Copyright 2003 by Cell
Press
你要的话需要跟corresponding author联系。 |
|
m********3
发帖数: 2125 | 7 当然是你买回去自己标记。
比如你有free amine的基团，然后买些succinimidyl ester的染料去标记。
如果有什么特殊的要求买不到的话，可以跟我合作。 |
|
j***j
发帖数: 560 | 8 Chemistry--An Asian Journal, 6(3), 932-937; 2011
Rhodium-Catalyzed 1,4-Addition of Lithium 2-Furyltriolborates to Unsaturated
Ketones and Esters for Enantioselective Synthesis of γ-Oxo-Carboxylic
Acids By Oxidation of the Furyl Ring with Ozone (pages 932–937)
Dr. Xiao-Qiang Yu, Tomohiko Shirai, Dr. Yasunori Yamamoto and Prof. Dr
. Norio Miyaura
Thanks in advance.
l***[email protected] |
|
O*******f
发帖数: 926 | 9 (1)先google关键词，比如“convert ester to methylketone”或者“Buchwald
ligand for ArNH2”，(2)然后找到对应的文献，记录下来，（3）上BBS或者其它论坛
，发贴求助文献。you are all set!
楼上提到的 (2) http://www.organic-chemistry.org，是个很好的资源库。至于那个 (1) COT，应该用第二版的了吧。既然提到了 COT，那么还应该提到 eROS（Encyclopedia of Reagents for Organic Synthesis）以及其增订版。 |
|
w*****n
发帖数: 214 | 10 Thanks for your reply first.
I have not tried in reagent methnol, but I believe even after the acid form
methyl ester with methnol, it still will be replaced with intra molecular
hydroxy group to form the lactone again during concentration. |
|
f*****n
发帖数: 1324 | 11 应该和一般的玻璃都不反应。
和塑料的话，要看是什么塑料。 氯气的氧化能力还是挺强的，有一点水的话生产HCl的
酸性也很corrosive，但是普通的PE, PP 应该是不怕这些的。有苯环的和ester bond的
塑料可能会反应？
抛砖引玉，说错勿怪。 |
|
q****e
发帖数: 3660 | 12 Ester alkoxylation technology
Weerasooriya, Upali. Journal of Surfactants and Detergents vol 2, no. 3 (Jul
1999): 373-381.
Thank you! |
|
G***O
发帖数: 839 | 13 非得用水相？acryloyl chloride 太活泼了，聚合都不需要加热，氮气保护加避光可能
会好点，最好还是用acid或phenyl ester。溶剂最好THF。acn 都可以。
你的基础有点弱，不过有机也没啥前途，做了10多年最后连工作都没有。哎。 |
|
g*****x
发帖数: 3283 | 14 你可以试着把NHS ester换成phosphoramidite，反应条件可能不那么mild。
另外如果需要很高的selectivity的话，基本只能在CPG上做了 |
|
x********g
发帖数: 595 | 15 [email protected]/* */
谢谢！
A Heterogeneous Niobium(V) Oxide Catalyst for the Direct Amidation of Esters
DOI: 10.1002/cctc.201500601 |
|
|
t******e
发帖数: 196 | 17 哪位大侠帮忙找一下这篇文献？多谢了！
Selective demethylation of phosphorus esters
Michael D.M. Gray, David J.H. Smith
Tetrahedron Letters
Volume 21, Issue 9, 1980, Pages 859-860 |
|
d********y
发帖数: 176 | 18 http://onlinelibrary.wiley.com/doi/10.1002/masy.19900320118/pdf
On the nature of active species in cationic ring-opening polymerization of
cyclodimethylsiloxanes
Authors
Pierre Sigwalt,
Vivian Stannett
First published: February 1990Full publication history
DOI: 10.1002/masy.19900320118View/save citation
Cited by: 5 articlesCitation tools
Abstract
Contrarily to cationic ring-opening polymerization of cyclic ethers and of
some other cyclic monomers, for which direct identification of the various
t... 阅读全帖 |
|
d********y
发帖数: 176 | 19 http://onlinelibrary.wiley.com/doi/10.1002/masy.19910420119/pdf
Article
Inhibiting or cocatalytic effect of water and other additives on cationic
polymerization of cyclodimethylsiloxanes
Authors
P. Sigwalt,
C. Gobin,
P. Nicol,
M. Moreau,
M. Masure
First published: March 1991Full publication history
DOI: 10.1002/masy.19910420119View/save citation
Cited by: 14 articlesCitation tools
Funding Information
Abstract
Cyclodimethylsiloxanes such as hexamethylcyclotrisiloxane (D3) and
octamethyl-cyclotetr... 阅读全帖 |
|
k****n
发帖数: 3803 | 20 ☆─────────────────────────────────────☆
heing (RP大爆发！) 于 (Tue Oct 23 21:00:33 2007) 提到:
发信人: windchina (future), 信区: JobHunting
标 题: 我一个半月的找工作经历(土木方向)
发信站: BBS 未名空间站 (Sun Jun 24 16:39:48 2007)
近来经常到这个版上来，得到XDJM们热心帮助。 为了表示感谢，现在把我过去一个半
月找工作的经历汇报一下。 希望对后来者有一些帮助。
我五月初开始找工作，拿到五个offer，公司都是中大型以上，on-site 成功率100％。
我本来在读PhD，但三四月份发生了一些很不开心的事情。 简单地说，就是博士导师
水平太差，系里的氛围也很不好，读不下去了。于是五也初决定quit PhD，正式开始找
工作。 对我来说，这是一个很困难的决定，毕竟读PhD是我的一个心愿，虽然这个学位
对我将来并不见得有太大帮助。
下定决心后，开始写简历，修改简历，然后把简历放在网上。monster.com 和
careerb... 阅读全帖 |
|
t***m
发帖数: 114 | 21 Polymere Abbreviations
ABA Acrylonitrile butadiene acrylate
ABS Acrylonitrile butadiene styrene
ABS alloys ABS alloys
ACM Acrylic acid ester rubber
ACS Acrylonitrile chlorinated PE styrene
AES Acrylonitrile-ethylene/propylene-styrene rubber
AMMA Acrylonitrile methyl methacrylate
AN Acrylonitrile
AO Antioxidant
APET Amorphous polyethylene terephthlate
APP Atactic polypropylene
ASA Acrylonitrile styrene acrylate
ASA alloys ASA/PC, ASA/AES etc
ATH Aluminum trihydrate
AZ(O) Azodicarbonamide
BDS Buta |
|
a***n
发帖数: 578 | 22 CH3OH
-[ Si ]-
is it what you got? Does this materials have a lot of porous?
Did you use STM to look at it?
ester may not dissociate under base condition. |
|
b**m
发帖数: 18 | 23 请问有没有什么好的书或者文章关于polycarbonate, epoxy resin, polyester,
polyamideimide, fluropolymer, acrylic ester, silicon, 以及 silicon rubber 在高
湿度(humidity)下的行为吗？以及它们是否和水缓慢反应。
先行谢过！！ |
|
b**s
发帖数: 589 | 24 you mean Polyacrylic ?
What property? |
|
r******0
发帖数: 2753 | 25
The difference between alchol and ester is much larger than alchol and ether.
~~~~
C-NMR may be more sensitive on this case.
I do hope you are right. Low MW polymer and very good NMR might tell the
difference. What I did is give you other possibilities that you may need
consider. Another suggestion is to order some very low MW poly(ethylene
glycol) and see if you NMR can see the chain end. If yes, you are right; if
not, :(
overlap.
ends
good |
|
w********h
发帖数: 12367 | 26 sorry, my mistake.
that should be a ester bond instead of ether in my initial question.
the difference between:
* * *
polymer-CO-CH2-CH(CH3)-OH
O
polymer-CO-CH2-CH(CH3)-OC-polymer
O O
I want to know if that -OH group can affect the chemical shifts of those three
protons with *.
thanks for your help...
ends
ether.
The
OH. |
|
x**j
发帖数: 1261 | 27 我用硫酸酸解t-butyl ester好像没有TFA好
- |
|
a*****h
发帖数: 13 | 28 t-butyl ester group seems to be quite stable in basic conditions, while not
stable in acidic conditions. I once tried to remove the t-butyl groups by
CH3ONa it didnot work, or very less amount of tButyl groups were destroyed |
|
m*****e
发帖数: 1506 | 29 应该很难吧，nBA和VAc都是ester unit，况且彻底水解VAc得用醇钠，不太好找到
selective deprotection的条件 |
|
r******0
发帖数: 2753 | 30 看你有些什么具体要求了。图方便的话，butonal 做溶剂，两三倍量的n-BtONa加进去
开煮。愿意多试一下的话，可以用butonal 做溶剂，加金属催化剂（如：MgTi(OC34H9)
6, Zn(OCH3)2....)
You can find a list of ester exchange catalyst from synthesis handbook. |
|
a*i
发帖数: 1652 | 31 interesting discussion on ester exchange reaction.
I am wondering how efficient the reaction is. Can PnBA-PVA obtained in the
end? Why doesn't exchange happen between PnBA and PVAc, resulting in
xlinking in the polymer? |
|
a********c
发帖数: 60 | 32 Please ignore my earlier comment, which was wrong. Whoever designed
ester-exchange route is a cleaver one. |
|
m*****e
发帖数: 1506 | 33 The easy way is to polymerize F-containing vinyl monomers from an OH-
functionalized initiator by ATRP, or from an OH-containing transfer agent by
RAFT.
Anionic polymerization followed by end capping with epoxide is the most
efficient way.
ROP of cyclic ester is also a common way to introduce OH- chain end, but you
need to synthesize F-containing monomer |
|
z*******o
发帖数: 136 | 34 PEG-OH + CF3SO2OSO2CF3(trifluoromethanesulfonic anhydride)+2,6-Di-tert-
butylpyridine(a hindered base to trap proton)-->PEG-O-SO2CF3(Triflate ester)
(室温搅拌反应，溶剂是CH2Cl2)
R-OH，如果R是烷基，那么这个反应很容易进行。我设计得R是PEG，试了很多次都不成
功。
从反应后的GPC分析看，所得高分子的分子量比起始反应的PEG的还低，感觉上去像是
PEG在反应体系下分解了，非常不解~
希望大家能给些建议，谢谢！ |
|
m*****e
发帖数: 1506 | 35 你的PEG多大？
用GPC定分子量不准确，因为size差别不大
应该用NMR看端基，或者mass spec
ester) |
|
m*****e
发帖数: 1506 | 36 RAFT copolymerization of MMA+MMAA should work.
Need a dithiol ester based CTA with an active leaving group producing a
tertiary radical.
There are references. |
|
|
J*****n
发帖数: 179 | 38 Hi folks
I'm looking for organic solvents which can form strong hydrogen bond with
the oxygen of carbonyl(C=O) in ester group. Do you guys know some candidates?
Thanks for help in advance. |
|
t****1
发帖数: 232 | 39 Depends on your ester group... I have experience of H-bonding of n-butanol
and methacrylates/acrylates, even the OH group in monomer can form H-bonding
with carbonyl group. |
|
发帖数: 1 | 40 本人多年从事polymer chemistry, organometallic, nanomaterials的研究工作，最近
在展审稿数量申绿，求推荐。以下是我的研究领域：
• Strong proficiency in design multi-step organic/organometallic/
inorganic syntheses under the various conditions, design of synthetic
strategy based on goal compound, cultivation of single crystals, synthesis
and characterization of organometallic compounds (Pd, Al, Sc, Y, Ti, Zr, Hf,
Fe, Co, Ni, Cr, Ir, Ru), macromolecules and nanomaterials:
1. Cross-Coupling polymerization: design, synthesis an... 阅读全帖 |
|
发帖数: 1 | 41 本人多年从事polymer chemistry, organometallic, nanomaterials的研究工作，最近
在展审稿数量申绿，求推荐。以下是我的研究领域：
• Strong proficiency in design multi-step organic/organometallic/
inorganic syntheses under the various conditions, design of synthetic
strategy based on goal compound, cultivation of single crystals, synthesis
and characterization of organometallic compounds (Pd, Al, Sc, Y, Ti, Zr, Hf,
Fe, Co, Ni, Cr, Ir, Ru), macromolecules and nanomaterials:
1. Cross-Coupling polymerization: design, synthesis an... 阅读全帖 |
|
s******n
发帖数: 4 | 42 大家讨论一下吧。
A 20-year-old woman develops severe pain and erythema over sun-exposed skin
and large bullae over her
shoulders while vacationing in Florida. Skin testing results in major
positive reactions to methylparaben, which is
often used as a preservative in medicines. A sunscreen containing which of
the following is CONTRAINDICATED
in this patient?
o A) Avobenzone
o B) Benzophenones
O C) Cinnamates
o D) p-Aminobenzoic acid esters
o E) Salicylates
BTW，有人下个月考试吗？一起复习吧。 |
|
y*******n
发帖数: 10103 | 43 机油分5个group，group I-III都是石油提炼的， Group IV base stock are
polyalphaolefins (PAOs). Group V is a catch-all group for any base stock not
described by Groups I to IV. Examples of group V base stocks include polyol
esters, polyalkylene glycols (PAG oils), and perfluoropolyalkylethers (
PFPAEs). Groups I and II are commonly referred to as mineral oils, group III
is typically referred to as synthetic (except in Germany and Japan, where
they must not be called synthetic) and group IV is a synthetic oil. G |
|
w******x
发帖数: 4396 | 44 种类多了去了，有的是纯r134，有的加了pag(46/100/150),有的加了ester。不能随便
混的。 |
|
w*******y
发帖数: 60932 | 45 Disney Halloween Treat Bag Art Kit $4.35 free shipping with Prime (FSSS)
from Amazon
Eeyore O'lantern
Contains: One permanent ink screen printed,poly ester/cotton pillowcase, 16
non/toxic crayons & instructions . Adult supervision required for heat
setting .
A welcome gift for any friend,packa ged in a wonderful gift box.
Approx. size 20'x30"
Link:
http://www.amazon.com/gp/product/B001GSLNHO/ref=ord_cart_shr?ie=UTF8&m=ATVPDKIKX0DER
|
|
w*******y
发帖数: 60932 | 46 Vitamin World:
http://www.vitaminworld.com/
is offering 60% off using promotional code VW270.
- you must call 866-667-8977
- you need to have a VW passport number (its a rewards card that you get
once you order)
- refer to THIS THREAD for more info on the Vitamin World promotion
Puritan's Pride:
http://www.puritan.com/
is offering B1G1 and B2G3
- no code necessary
- you might be able to stack with additional money off (can not confirm as
I haven't tried it)
I am only doing a comparison on th... 阅读全帖 |
|
w*******y
发帖数: 60932 | 47 Hi Folks..there are a lot of places where u can get flu shots, but being the
that we are....we need a 'deal' to go with it...so I am compiling the flu
shots 'DEALS' happening this year, as a for one stop reference for s..
1. Safeway group (Tom Thumb, Safeway etc) have a deal where you get 10% off
your groceries if you get flu shots through them...
http://www.safeway.com/IFL/Grocery/Flu-Shots
2. Rite Aid
to thearteest, Rite is giving away a coupon book and 25 wellness points...
see this threa... 阅读全帖 |
|
w*******y
发帖数: 60932 | 48 GASPARI NUTRITION - IntraPro Delicious Vanilla 5 lbs $26.99+ $5.95 s/h
Link:
http://www.allstarhealth.com/f/gaspari_nutrition-intrapro.htm
Supplement Facts
Serving Size: 1.00 scoop(36g)
Servings per Container: 63.00
Ingredient Amount % Daily Value**
Calories 155
Calories from Fat 31.5 5
Total Fat 3.5g 5
Saturated Fat 0.5g 2
Trans Fat 0
Cholesterol 45mg 15
Sodium 70mg 3
Potassium 150mg 4
Total Carbohydrates 5g 2
Dieta... 阅读全帖 |
|
w*******y
发帖数: 60932 | 49 I haven't used this stuff yet myself but just ordered 5 based upon
recommendations and the sale price on the 35 servings tub. Also, the 9.2
rating on BB.com seems pretty reassuring.
Keep in mind the website gives away a selection of free gifts for orders
over $75, $100, and $150 price points. You will see this clearly as you
order, better gifts the more you spend obviously.
Shipping seems to be between 7-10$ for me depending on what I had in my cart
, but the shipping went up very little with ... 阅读全帖 |
|
v**********m
发帖数: 5516 | 50 楼上文章的comments
Not yet but stay tuned. But a definite fact and you can review it in the FDA
's analysis in the briefing document is that there was no SS of astrocytomas
in male rats or female rats.
Dr. Alavi had concerns about how Arena calculated the exposure margin for
Lorcaserin, that is why it appeared in the CRL. When Arena met directly with
the FDA on December 15th and 16th at the FDA, both Arena and the FDA agreed
on the CSF methodology and the number of participants that would be
acceptab... 阅读全帖 |
|
