萘并呋喃类化合物的染料化光氧化及其杂环衍生物的合成与表征

萘并呋喃类化合物1、7在四苯基卟啉存在与氧低温反应给出相应的二氧杂环丁烷类产物2、8，室温下分别全部分解成乙酰基乙酰氧基化合物4、9。2和盐酸作用可给出呋喃3-位甲基及所在萘半环β位的二氯代产物6。4与盐酸反应通过失去萘α位的酰基，形成羟基呋喃化合物3，1在三溴化硼酸解下亦可得同一产物。4在醋酸钠/酸酐中环构生成3-乙酰基吡喃酮(5)。     

N-苯基和N-乙氧羰基甲基磷异喹啉酮及其衍生物的合成

以邻炔基苯磷酰胺为原料经Pd(II)催化的环化反应、环化偶联反应和氯环化反应高收率合成了15个N-苯基和N-乙氧羰基甲基磷异喹啉酮及其4-烯丙基、4-氯衍生物, 它们的结构均经过1H NMR, 13C NMR, MS, IR及元素分析确证.     

Kaminsky型催化剂催化乙烯环齐聚反应的研究

研究发现Cp~2ZrL~2(L=Cl,Me,OC~6H~4-p-Me)/EAO(乙基铝氧烷)可同步催化乙烯齐聚-环化反应,不仅给出链状烯烃,而且生成环状剂聚物－－亚甲基环戊烷。环状齐聚物的选择性取决于主催化剂的结构和浓度,反应介质,预反应温度和反应温度,反应时间,Al/Zr比及烷基铝水解程度等因素,加入碱性第三组分对催化活性和选择性亦有一定影响。在优化反应条件下,亚甲基环戊烷的选择性达到37%。     

Efficient synthesis of 2,5-diketopiperazines using microwave assisted heating

In this study a general, efficient and environmentally benign solution phase synthesis of 2,5-diketopiperazines (DKPs) using microwave assisted heating in water is described. A series of 11 structurally different DKPs have been synthesized from dipeptide methyl esters. A range of common laboratory solvents have been tested as well as different reaction times and temperatures. Both classic thermal and microwave assisted heating have been investigated. Microwave assisted heating for 10 min using water as solvent proved, by far, to be the most efficient method of cyclization giving moderate to excellent yields (63-97%) of DKPs. In contrast to other published procedures, this method seems independent of the amino acid sequence.     

Synthesis of α-CF3 azanorbornene and azetidines by aza Diels–Alder or iodine-mediated cyclizations: application in ROMP and ligand design

We report the synthesis of several new α-trifluoromethylated nitrogen heterocycles, among which azanorbornene and azetidine derivatives, by aza Diels–Alder or iodine-mediated cyclizations. These building blocks were used as starting materials for the formation of fluorinated polymers by ROMP or for ligand design through substitution and click reactions.     

Cyclizations of Alkenyl(Alkynyl)-Functionalized Quinazolinones and their Heteroanalogues: A Powerful Strategy for the Construction of Polyheterocyclic Structures

Quinazolin-4-one, its heteroanalogues, and derivatives represent an outstandingly important class of compounds in modern organic, medicinal, and pharmaceutical chemistry, as these molecular structures are noted for their wide synthetic and pharmacological potential. In the last years, ever-increasing research attention has been paid to quinazolinone derivatives bearing alkenyl and alkynyl substituents on the pyrimidinone nucleus. The original structural combination of synthetically powerful endocyclic amidine (or amidine-related) and exocyclic unsaturated moieties provides a driving force for cyclizations, which offer an efficient toolkit to construct a variety of fused pyrimidine systems with saturated N- and N,S-heterocycles. In this connection, the present review article is mainly aimed at systematic coverage of the progress in using alkenyl(alkynyl)quinazolinones and their heteroanalogues as convenient bifunctional substrates for regioselective annulation of small- and medium-sized heterocyclic nuclei. Much attention is paid to elucidating the structural and electronic effects of reagents on the regio- and stereoselectivity of the cyclizations as well as to clarifying the relevant reaction mechanisms.     

Some interesting C<Emphasis Type="Italic">H</Emphasis><Subscript>2</Subscript>C<Emphasis Type="Italic">H</Emphasis><Subscript>3</Subscript> spin systems in several diethyl malonate indene derivatives studied with NMR and molecular modeling

While studying the electrophilic cyclization of acetylenic malonates in synthesizing malonate indene derivatives with high regio and stereo-selectivity, we found that the CH₂ and CH₃ protons of two COOCH₂CH₃ groups in some diethyl malonate indene derivatives showed very interesting spin-spin coupling and signal multiplicity. To explain those phenomena, we synthesized several diethyl malonate indene derivatives, and then used ¹H NMR spectra and molecular modeling to investigate the CH ₂CH ₃ spin system of these two COOCH₂CH₃ groups in detail. The results showed that the spin systems of CH ₃CH ₂ of the two COOCH₂CH₃ groups in those compounds may exist in different froms (AMX ₃, ABX ₃ and A ₂ X ₃), and the effect of the aromatic ring induced by the phenyl group at the end of the triple bond is the main reason responsible for those phenomena.     

Palladium-catalyzed carbonylative cyclization of 2-bromobenzaldehyde with primary amines leading to isoindolin-1-ones

2-Bromobenzaldehyde is carbonylatively cyclized with primary amines under carbon monoxide pressure in DMF at 100 °C in the presence of a catalytic amount of a palladium catalyst to give the corresponding isoindolin-1-ones in moderate to high yields.