N,N'-Dimethylurea as an efficient ligand for the synthesis of pharma-relevant motifs through Chan-Lam cross-coupling strategy.

N,N'-Dimethylurea (DMU) is introduced as a ligand to aid the Chan-Lam N-arylation of primary amides, amines, and 3-aminophenols with arylboronic acids and its ester derivative as the arylating associate. The developed methodology is catalyzed by Cu and its in situ complexation with DMU brings about efficient synthesis of N-arylated anilines, 3-aminophenols, and primary amides in moderate to good yields (50-90%). The [Cu2(OAc)4(DMU)2] complex is synthesized and characterized by single crystal structure elucidation. The catalyst is cheap, free from prior synthesis of a metal complex, provides chemoselectivity towards the N-arylation of 3-aminophenols, and is suitable for mono-arylation of primary amides. The synthetic utility of the methodology is tested in the post-modification of two active pharmaceutical ingredients (APIs). The developed catalytic system extends the scope of N,N'-dimethylurea as an auxiliary in inexpensive and versatile Cu catalysis.

Revisiting the synthesis of aryl nitriles: a pivotal role of CAN.

Facilitated by the dual role of Ceric Ammonium Nitrate (CAN), herein we report a cost-effective approach for the cyanation of aryl iodides/bromides with CAN-DMF as an addition to the existing pool of combined cyanation sources. In addition to being an oxidant, CAN acts as a source of nitrogen in our protocol. The reaction is catalyzed by a readily available Cu(ii) salt and the ability of CAN to generate ammonia in the reaction medium is utilized to eliminate the additional requirement of a nitrogen source, ligand, additive or toxic reagents. The mechanistic study suggests an evolution of CN- leading to the synthesis of a variety of aryl nitriles in moderate to good yields. The proposed mechanism is supported by a series of control reactions and labeling experiments.

Trinuclear Mn2+/Zn2+ based microporous coordination polymers as efficient catalysts for ipso-hydroxylation of boronic acids.

Two microporous coordination polymers based on hourglass trinuclear building units, [Mn3(bpdc)3(bpy)]·2DMF and [Zn3(bpdc)3(bpy)]·2DMF·4H2O (bpdc = 4,4'-biphenyl dicarboxylic acid, bpy = 4,4'-bipyridine), have been synthesized under solvothermal conditions employing DMF as the solvent. Each structure consists of two crystallographically distinct M2+ (M1 and M2) centers that are connected via carboxylate bridges from six bpdc ligands, generating a trinuclear metal cluster, [M3(bpdc)3(bpy)]. Cluster representation of the structure resulted in an interpenetrated net of rare hex topological type. Catalytic activities of the CPs have been assessed for the oxidative hydroxylation of phenylboronic acids (PBAs) using aqueous hydrogen peroxide (H2O2). Various substituted aryl/hetero-arylboronic acids RB(OH)2 [R = phenyl, 2,4-difluorophenyl, 4-aminophenyl, 2-thiophene etc.] underwent ipso-hydroxylation smoothly at room temperature to generate the corresponding phenols in excellent yields. The main advantages of this protocol are the aqueous medium reaction, heterogeneous catalytic system, and short reaction time with excellent yield.

Greener Biogenic Approach for the Synthesis of Palladium Nanoparticles Using Papaya Peel: An Eco-Friendly Catalyst for C-C Coupling Reaction.

The development of a green and sustainable synthetic methodology still remains a challenge across the globe. Encouraging the prevailing challenge, herein, we have synthesized Pd nanoparticles (Pd NPs) in a green and environmentally viable route, using the extract of waste papaya peel without the assistance of any reducing agents, high-temperature calcination, and reduction procedures. The biomolecules present in the waste papaya peel extract reduced Pd(II) to nanosize Pd(0) in a one-pot green and sustainable process. As a catalyst, the new Pd NPs offer a simple and efficient methodology in direct Suzuki-Miyaura and Sonogashira coupling with excellent yields under mild reaction conditions.

A one pot, two-step synthesis of 5-arylpyrrolo[2,3-d]pyrimidines and screening of their preliminary antibacterial properties.

A one pot two step methodology for the synthesis of ten derivatives of 5-arylpyrrolo[2,3-d]pyrimidine has been reported. The methodology exploits the strong reducing nature of alkaline Na2S2O4 solution coupled with favorability of Michael type addition reaction in alkaline medium. The methodology demands attraction as it is non-catalytic, quite general for wide range of nitrostyrenes and possesses comprehensive advantages over most of the earlier methods in terms of reaction time as well as yield. The methodology enjoys additional advantage of utilizing cheaper and easily available chemicals as reagent for the purpose. Some of the synthesized compounds are found to possess remarkable activity against some of the tested bacterial strains.

Nanorod-Shaped Basic Al2O3 Catalyzed N,N-Diformylation of Bisuracil Derivatives: A Greener "NOSE" Approach.

A feasible "NOSE" (nanoparticles-catalyzed organic synthesis enhancement) protocol has been developed for N,N-diformylation of bisuracil derivatives using nano-Al2O3 rods as an efficient, inexpensive, and recyclable catalyst under solvent-free reaction condition at 40°C. The catalyst was reused up to the 4th cycle without affecting the rate and yield of the N,N-diformylation products appreciably.

Piper-betle-shaped nano-S-catalyzed synthesis of 1-amidoalkyl-2-naphthols under solvent-free reaction condition: a greener "nanoparticle-catalyzed organic synthesis enhancement" approach.

Nano-S prepared by an annealing process showed excellent catalytic activity for the synthesis of 1-amidoalkyl-2-naphthols under solvent-free reaction condition at 50 °C. The catalyst could be reused up to the fifth cycle without loss in its action. The green-ness of the present protocol was also measured using green metrics drawing its superiority.

6,6'-Diamino-1,1',3,3'-tetra-methyl-5,5'-(4-chloro-benzyl-idene)bis-[pyrimidine-2,4(1H,3H)-dione].

The title compound, C(19)H(21)ClN(6)O(4), is a 1:2 adduct of p-chloro-benzaldehyde and uracil. It crystallizes with two mol-ecules in the asymmetric unit. The two uracil units in the same mol-ecule are connected by a pair of strong N-H⋯O hydrogen bonds. The packing is stabilized by N-H⋯O, C-H⋯O and C-H⋯N inter-actions.

6-[(Dimethyl-amino)methyl-ene-amino]-1,3-dimethyl-pyrimidine-2,4(1H,3H)-dione dihydrate.

Uracil, the pyrimidine nucleobase, which combined with adenine forms one of the major motifs present in the biopolymer RNA, is also involved in the self-assembly of RNA. In the title compound, C(9)H(14)N(4)O(2)·2H(2)O, the asymmetric unit contains one dimethyl-amino-uracil group and two water mol-ecules. The plane of the N=C-NMe(2) side chain is inclined at 27.6 (5)° to the plane of the uracil ring. Both water mol-ecules form O-H⋯O hydrogen bonds with the carbonyl O atoms of the uracil group. Additional water-water hydrogen-bond inter-actions are also observed in the crystal structure. The O-H⋯O hydrogen bonds lead to the formation of a two-dimensional hydrogen-bonded network cage consisting of two dimethyl-amino-uracil groups and six water mol-ecules.

Regiospecific one-pot synthesis of pyrimido[4,5-d]pyrimidine derivatives in the solid state under microwave irradiations.

Electron rich 6-[(dimethylamino)methylene]amino uracil 1, undergoes [4+2] cycloaddition reactions with various in situ generated glyoxylate imine and imine oxides 6 to provide novel pyrimido[4,5-d]pyrimidine derivatives of biological significance, after elimination of dimethylamine from the (1:1) cycloadducts and oxidative aromatisation. This procedure provides a convenient method for the direct synthesis of pyrimido[4,5-d]pyrimidines in excellent yields when carried out in the solid state and under microwave irradiations.