Five days later.
USTC dical Center Building, a drug chemistry laboratory on the fourth floor.
At this mont, Xu Yun was wearing a cotton lab coat, standing at the workbench, with six n and won of varying heights standing in front of him.
"Since everyone is here, I’ll just say a few words."
Xu Yun waved a stack of bound docunts in his hand, his gaze quickly sweeping over the people in front of him:
"Yesterday morning, I received the project initiation receipt. Now, we have results for procedures, venue, and personnel, so our research group is established.
Our research group doesn’t have a supervisor leading it; I’m the applicant and the person chiefly responsible. The lab usage period is two weeks, and the participation records will be noted in your files. Whether there’s a result or not, it can count as a comndable credential, which should help all of you to so extent in the future."
Upon hearing this, two of the six people in front of him instantly showed an uncontrollable hint of delight on their faces.
As a mber of C9, USTC’s annual research funding is about a hundred billion, ranking dostically around ninth or tenth.
Although this number seems large, after deducting projects like 973 Program, 863 Program, National Science and Technology Support Program, and International Science and Technology Cooperation and Exchange Special Program, the funding and spots allocated to each departnt are far less than they appear.
Then, after being divided by so big shots, there is funding left, but not many high-quality project slots.
Many graduate students toil away for one or two sesters and still may not touch the edge of major projects, silently used by their supervisors like a donkey.
Thus, when Xu Yun ca with Tian Liangwei’s subsidiary project initiation slip, several struggling graduate students imdiately nodded with excitent, their vibration frequency like a massager, almost needing Xu Yun to say that Huaxia People don’t deceive Huaxia People.
To put it bluntly, participating in such a level of project group, regardless of the end result, one can ask for at least an additional five hundred yuan a month when reporting pay after graduation!
Then Xu Yun paused and continued:
"The goal of our project is quite simple—to try synthesizing pheromones and third-generation imidacloprid into a new substance, to verify and explore the direction of fourth-generation imidacloprid. The ultimate goal is..."
As soon as the words fell, several juniors and juniors shouted in unison:
"Exterminate cockroaches!"
After saying this, everyone laughed joyfully.
In the laughter, a girl with short hair raised her hand, looking curiously at Xu Yun and asked:
"Senior, why do you have such a big grudge against cockroaches?"
Xu Yun lightly glanced at her; this girl was nad Tang Yiqiu, an undergraduate senior with good grades and reputation:
"...To , it’s a sad story, but if spoken out it would make you very happy, so I refuse to answer."
Finishing, he waved the docunts in his hand, the paper rattling in the air:
"Okay, that’s enough chit-chat. We have limited ti. Everyone check your gas masks and organic vapor filter cartridges. Wear your protective gowns; we’ll start the experint in fifteen minutes!"
Then he gave Qiu Sheng a look:
"Old Qiu, check the machines and circuit breaker, I’ll go distribute the materials."
Qiu Sheng nodded:
"Understood."
Fifteen minutes later, everything was ready.
The main experintal reagents for Xu Yun and others this ti were 2-phenylpyridine, 4-hydroxythylphenylboronic acid, 2-naphthylboronic acid, 3-furanboronic acid, 3-benzothiophene boronic acid, N-phenylpyrazole, benzoquinoline, [Ru(p-cyne)2Cl2]2, etc.
Moreover, there were over thirty reagents including 2-bromopyridine, 2-bromo-4-chloropyridine, THF, DMF (N, N-dithylformamide), DMSO, 1,4-dioxane, et cetera (specifically written in the author’s words).
anwhile, the others also took position in their respective spots.
"To combine pheromone with imidacloprid, the first step is to cyclize CH3. I plan to complete this via the hydrogenation reaction of epoxide end alkynes and 1-bromo-2-pentyne coupling."
At the workbench, Xu Yun expressed his thoughts while addressing one of the underlings...oops, juniors:
"Li Yi, this task is yours."
"Understood!"
The Li Yi Xu Yun ntioned was a graduate student, 24 years old, with a crew cut, and he imdiately began the operation upon hearing.
anwhile, Xu Yun looked at Tang Yiqiu:
"Xiaotang, you track and attempt to capture the optically active fragnt of epoxide sulfonate!"
"Understood!"
It is well-known.
Under the catalysis of L-( )-diisopropyl tartrate and tetra-isopropyl titanate, allyl alcohol undergoes Sharpless asymtric epoxidation, yielding (2S, 3R)-2,3-epoxy-1-tetradecane alcohol.
Epoxy alcohol (2S, 3R)-9, after p-toluenesulfonylation and perchloric acid ring-opening, flips the absolute configuration of the 3-carbon atom from R to S, yielding (2S, 3S)-p-toluenesulfonic acid 2,3-dihydroxy-1-tetradecane alcohol ester; then, after potassium carbonate cyclization and p-toluenesulfonylation, it further yields (2S, 3S)-p-toluenesulfonic acid 1,2-epoxide 3-tetradecane alcohol ester, with a yield of up to 89%.
Very simple, and very easy to understand.
A few minutes later, Tang Yiqiu raised her hand again, but this ti she didn’t ask about why Xu Yun wants to exterminate cockroaches:
"Senior, we’ve captured the epoxide sulfonate!"
"Great, what’s the ee value?"
"Still asuring.....epoxy alcohol and dinitrobenzoyl chloride are still reacting...oh, it’s out, 93%!"
Upon hearing this, Xu Yun couldn’t help but let out a breath.
The so-called ee value refers to enantioric excess; the theoretical ee value of chiral epoxide sulfonate is 90%. Xiaotang asured 93%, which is above the standard line, currently marking a successful small step.
After synthesizing the critical optical active interdiate, the next step is the asymtric synthesis of targeted pheromones.
This step involves reacting epoxide sulfonate with trithylsilyl acetylene, undergoing epoxide ring-opening, and after potassium carbonate treatnt, cycling and de-TMS, yielding (4S, 5R)-4,5-epoxy-1-hexadecene alkyne, with a yield of.....
60%.
That’s right, first step 89%, second step 60%.
Almost halved the yield.
This is a very common situation in biochemistry; the yield gets lower as it goes forward, from 90% to 60%, then continuing to 30%.
Through seven or eight cycles, very abnormal compounds might have single-digit yields.
That’s why research is money-consuming—Xu Yun and his group spent at least 1000 yuan in the first ten minutes, including machine wear, a whole Alliance Leader.
The preparation of 5-epoxy-1-hexadecene alkyne went smoothly, and just when Xu Yun and others were about to proceed to the next step...
Another graduate student responsible for nucleophilic substitution suddenly let out an "ah", sighing:
"Senior, the nucleophilic substitution reaction failed..."
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