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Transition Metal-Catalyzed Borylation of Aromatics

Thesis Info

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Author

Shahzadi, Hafiza Tayyaba

Program

PhD

Institute

Lahore University of Management Sciences

City

Lahore

Province

Punjab

Country

Pakistan

Thesis Completing Year

2019

Thesis Completion Status

Completed

Subject

Chemistry

Language

English

Link

http://prr.hec.gov.pk/jspui/bitstream/123456789/11470/1/Hafiza%20Tayyaba%20Shahzadi%20chemistry%202019%20lums%20lhr.pdf

Added

2021-02-17 19:49:13

Modified

2024-03-24 20:25:49

ARI ID

1676727630408

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Selective functionalization of hydrocarbons represents a long-standing challenge in the synthetic world. Transition metal-catalyzed reactions, such as transformation of C–H/ C– X bond to C–B bond has emerged as potent tool towards this goal during the last few decades. Especially the Ir-catalyzed aromatic C-H activation/borylaytion provides unique selectivity which is complemantary to those found in the traditional synthetic routes. Sterically governed regioselective control in this new synthetic tool allows the synthesis of (hetero)aromatic compounds which are difficult to access by the conventional routes. In the current work, we have utilized this methodology to gain facile access to new aromatic building blocks with better atom & step economy. One study presents the synthesis of hydroxybenzoates. Hydroxybenzoates are widely used as preservatives and antiseptics in the food and pharmaceutical industry. However, strategies focusing on the direct synthesis of 2,6- and 2,3-disubstituted hydroxybenzoates are lacking in literature. Herein we report an efficient protocol employing iridium-catalyzed C–H borylation/oxidation of commercially available benzoic acid/ester substrates. This route provides facile access to halogen decorated para-/meta-hydroxybenzoates as the synthesis of akin compounds is laborious by traditional approaches. Second project targets the synthesis of boscalid analogs. Boscalid is an extensively used fungicide for crop protection. Traditional routes of boscalid synthesis involve precursors that need pre-functionalization of arenes, which affects the step economy and overall efficiency. The aim of this study is to develop boscalid analogues from readily available hydrocarbon feedstock without pre-functionalization. Sequential Ir-catalyzed C–H borylation of arenes and Suzuki coupling provide biphenyl amines which on amidation produce boscalid analogues in good yield. Synthesized compounds are further evaluated by molecular docking to gain insight into the binding pocket of protein. The In-vitro studies of the analogs are carried out against Fusarium moniliforme and few of the synthesized compounds provided superior inhibition on potato dextrose agar (PDA) plates. Next, Ir-catalyzed C-H borylation of CF3 substituted pyridines is reported. The versatility of the methodology is demonstrated by the use of various substitution patterns in the substrate molecule. Based on the steric evaluation, selective positions of CF3 substituted pyridines are functionalized. Several functional groups like halo, ester, methoxy and amino are compatible with this methodology. Chiral boronic esters are indispensable building blocks owing to their versatile transformations and immense applications in medicinal and material chemistry. Herein, we also disclose Pd-catalyzed chiral borylation of aryl halides, whereby numerous substrates bearing broad range of functional groups are found to be compatible for the developed approach. Aryl/hetero aryl chiral boronic esters are obtained in moderate to excellent yield. The resulting chiral boronic esters can serve as significant precursors in asymmetric synthesis.
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39. Al-Zumar/The Companions

39. Al-Zumar/The Companions

I/We begin by the Blessed Name of Allah

The Immensely Merciful to all, The Infinitely Compassionate to everyone.

39:01
a. The sending down of The Book - The Qur’an - with meticulous care has been arranged by Allah - The One and Only God.
b. The Almighty, The All-Wise.

39:02
a. Indeed, WE have sent down to you, O The Prophet, The Book with the purpose of making it a decisive authority.
b. So submit to Allah in awe and worship,
c. sincere in your Faith in HIM alone.

39:03
a. Indeed the True Faith is for Allah alone.
b. Yet those who take up other entities as their protectors instead of HIM, argue:
c. ‘We do not worship them except that they may bring us close to Allah.’
d. Allah will certainly judge between them concerning their differences.
e. For sure, Allah does not guide anyone who is a liar and is ungrateful/disbelieving.

39:04
a. If Allah had ever wanted to take a son to HIMSELF,
b. HE could have certainly chosen whoever HE Willed from those whom HE created.
c. Glory be to HIM!
d. HE is Allah, The One and Only, The Prevailing.

39:05
a. HE created the celestial realm and the terrestrial world for a purpose and without a precedent.
b. HE wraps the nighttime around the daytime, and
c. wraps the daytime around the nighttime.
d. HE made the sun and the moon subservient to HIS laws to serve you, each running on a
fixed course in their respective orbits for an appointed term set by HIM.
e. Indeed, HE is The Almighty, The Ever-Forgiving.

متعہ كی لغوی تحقیق اورشرعی حیثیت تاریخی تناظر میں

This article deals with the issue of temporary marriage or "Mut'a" as is euplicated and regulated by Islamic Shariah in the early days of islam. Since those particular conditions did not prevail later, hence it became redundant. However, the term "Mut'a" has been used in the Holy Qur'an in multiple ways. Our scholarly interest focuses this particular dimension. Moreover a minor segment of Muslims still practice "Mut'a". However, the Sunni Scholars and followers have stopped practised on it. Iran e.g. still follows this temporary mode of marriage (they may opt to do so). However, according to Sunni traditions, this practice has been abolished. Hereby a scholarly investigation is done on "Mut'a", its terminology, its history its background and the particular conditionalities

A Co-Relation Study of Telomere Length and Genetic Predisposition to Acute Lymphoblastic Leukemia Among Pakistani Population

Acute lymphoblastic leukemia (ALL) is a hematological malignancy common in children and adult males. ALL is considered to be on the rise in Pakistan. External, physiological and genetic factors have been found to play a fundamental role in causing the cancer. In the present study, we investigated the external factors like exposure to radiations, chemicals, sunlight, smoking, electronic devices and dietary habits as potential risk factors in relation to ALL. None of these factors were found to be associated with ALL risk in Pakistani population. However, among physiological factors we found significant correlation between psychological stress and ALL incidence. Overrepresentation of B+ve blood group was noted among ALL patients. Replicative potential, telomere modulation, migration / metastasis, unlimited proliferation and metabolic reprogramming are important for tumor development. Genes including GMFG, EpCAM, PCSK9, CTC1 and OBFC1 were studied at transcriptional level to elucidate their role in ALL related to motility, proliferation, lipid metabolism and telomere modulation, respectively. The role of these genes in relation to ALL was not studied before. To study telomere modulation important for leukemia cell survival, telomere length measurement was performed. No significant changes in telomere length were observed. However, at transcriptional level, induced expression of telomere modulating genes (CTC1, OBFC1, hTERT) in ALL patients was observed which could be correlated with telomere length maintenance in leukemia cells. The induced GMFG expression, which is important for cell migration, in leukemia patients indicated that it has potential to be used as a leukemia diagnostic marker. EpCAM related to cell proliferation was not well established in ALL. Its mRNA expression was significantly upregulated in ALL patients. Similarly, PCSK9 which regulates cholesterol metabolism was also induced in ALL. mRNA expression of ALL specific genes like TAL1, BLNK and BLACE were also investigated and found to be upregulated in ALL Pakistani population. They, therefore, could potentially be used as ALL gene markers for early detection and diagnosis of leukemia. xii Next, in in vitro studies, naturally occurring biomolecules like costunolide and eugenol were used for identification of new therapeutic approaches with better treatment outcome. Costunolide, a potent telomerase inhibitor reduced EpCAM and its downstream target gene c-Myc and probably also contributed in inhibiting hTERT expression. Similarly, PCSK9 and LOX1 were significantly down-regulated by antioxidant eugenol. Results from this study suggested that costunolide and eugenol could plausibly be used as therapeutic biomolecules for reducing cancer cell proliferation and growth by limiting the metabolic supply.